Booster Cable Assembly: How to Use Them Safely and Successfully

Jumper cables with clamps

Your vehicle battery can die for several reasons, like low temperature.

You must start your car to drive it to the mechanic’s shop.

You may need a booster cable assembly to jump-start the battery.

What is a booster cable?

You can call a booster cable a jump lead or a jumper cable. 

This cable comprises a pair of insulated wires with alligator clips at both ends so it can interconnect the non-functioning equipment or vehicle to some auxiliary source.

The auxiliary can be another vehicle, equipment with the same voltage system, or another battery.

The alligator chips in the wires have proper insulation to avoid short circuits.

These clips are either made of copper or steel, and these chips have polarity markings in black (-) and red (+) colors.

You will find one black and one red cable in a booster assembly.

The colors help you to know where to attach the cables. In an electrical system, electric current flows from a negative terminal to a positive terminal through some wires to power something.

In this case, they will power the car’s starter.

Thus, you must connect the correct terminals to make your jumper cable work properly.

Always connect the red cable with the positive terminal and the black cable with the negative terminal. 

Remember not to touch the jumper cable to anything except the target.

Battery jumper cables

Battery jumper cables

Booster cable assembly considerations

When choosing a booster cable to work with your car, consider the following features.

Jumper cable gauge

Generally, jumper cables range from gauge 1 to gauge 12. According to this scale, Gauge 1 is a heavy-duty option, while the last one, i.e., gauge 12, is a light-duty option. 

As you know, thick cables carry more current; you can jump-start a battery faster with a thicker cable.

According to the industry recommendations, you must use a 4-gauge jumper cable for a dead battery.

However, to jump-start a drained battery in normal temperatures, you can use a 10-gauge cable.

Of course, most of the time, we choose the gauge according to vehicle types.

For cars, gauge 6 is enough; for bikes, you can do it with a gauge-10 wire as bikes do not need more power, and a smaller gauge is enough.

If you have a full-size or diesel truck, it is better to take the gauge-4 wire.

Apart from this, if you are handling something heavier than a truck with a couple of batteries, you can use gauge-1 or gauge-2.

Length

If two cars face each other, a 10 feet long cable is enough, but that is not always possible.

So always go to longer lengths for higher flexibility. Remember, as the cable length increases, the gauge decreases as less charge flows through the longer lengths.

Insulation

When you use a jumper cable in cold climatic conditions, you need an adequately insulated set of jumper cables; otherwise, the cables will break when you take them out.

In addition, insulation helps in preventing general wear and tear. If the cable gets damaged, it results in an arc formation, which can shock you or your car.

Clip material

The auxiliary clips on the jumper cable act as a clamp to ensure a solid connection to the battery. 

In the copper-plated clamps, the base metal is steel which is not a good conductor of electricity.

In addition, these clamps start wearing off over time, making loose connections.

On the other hand, even if the copper clamps scratch, they will continue working efficiently. 

Amperage

Starting a smaller car needs less amperage than starting a large truck or an SUV vehicle.

Generally speaking, 200 amperes is enough to provide the necessary power.

However, the industry recommends using not less than 400 amperes of cables.

You may need jumper cables with more than 600 amps for some very heavy vehicles.

Warranty

Always pick a jumper cable that covers a warranty and is UL certified. With such safety certificates, the company is there to help if anything goes wrong.

High-quality jumper cables

High-quality jumper cables

Safety tips for jumping start a car.

  • Read your car’s manual and look for specific car batteries or jump-start instructions. Some manufacturers suggest not to jump-start your car, while others give particular instructions to jump-start the car.
  • Look for the car battery. Most of the time, it is in the front portion, under the hood. However, in some car models, you may also find the battery in the trunk. If the battery’s location is in the trunk, find its designated terminals for use. 
  • Take note of the battery’s positive and negative terminals and ensure that you attach the jumper cables to the correct terminals to avoid accidents.
  • For the safer side, remove the keys from the car’s ignition (both cars if using the car for a jump start).
  • Make sure that nothing flammable is available near the battery. There are chances of sparks, fires, and explosions during jump start. The car batteries and portable jump devices have high voltages.
Jump start a car

Jumpstart a car

How To Jump Start a Car

There are two ways of jump-starting a dead battery: a portable jump battery or another vehicle.

Use jumper cables with another car.

  • Firstly, find out the location of the battery. Mostly, the battery is with the engine.
  • Secondly, park both cars close enough but without touching each other from anywhere; otherwise, the current will flow through different parts along with jumper cables.
  • Power off the engine of both cars. 
  • Note the battery’s positive (+) and negative (-) terminals and attach the jumper cable to the proper terminals. 
  • First, connect one side of the red jumper cable to the non-working battery’s positive terminal.
  • Secondly, connect the other end of the red cable to the positive terminal of the live car battery.
  • Third, attach one end of the back jumper cable to the negative terminal of the working car’s battery.
  • Finally, connect another end of the black cable to a piece of stationery metal on the car with the dead battery.
  • Remember not to join this terminal to the negative terminal of the non-working car’s battery.
  • Why? Some people consider it okay, but it increases the chances of fire and explosion if the jump start fails.
  • You can connect that part to the engine bolt, car’s chassis, alternator bracket, or a grounding terminal. 
  • When you finish all the connections, charging begins, and your vehicle may either start immediately or take some time.
  • Give some time for the engine to work and let current flow from the working battery to the dead battery.
  • After some time, try to start the car. Insert the key and turn it to start. Hold the key only for a few seconds and not more than that.
  • You may need to do this several times.
  • If your jump-start does work well, the engine will start. Once you drive the car for some time, it will automatically recharge the battery.
  • If you hear the engine cranking on turning the key, there may be another issue, and you may need to see the mechanic.
  • It would help to disconnect the jumper cables when your dead battery starts working. Ensure not to touch the cables to anything before you make all disconnections; otherwise, the current can go to some unwanted locations.
  • First, detach the black cable from the car’s chassis/bolt/terminal.
  • Second, detach another end of the black jumper cable from the negative terminal of the working car’s battery.
  • Third, detach the end of the red jumper cable from the working car’s battery’s positive terminal.
  • Finally, disconnecting its other end from the car’s battery’s positive terminal requires a jump start.
Jump-start a car with another car

Jump-start a car with another car

Use a portable jump starter.

  • You can also use portable jump starters/jump boxes or battery packs to jump-start your car if another car is unavailable.
  • As it is portable, you can keep it in the trunk, glove box, or anywhere else. However, most jump starters cannot bear very high summer temperatures.
  • So, read the instructions before you carry one into your car.
  • Switch off the starter. Also, ensure that all auxiliary features of your dead vehicle are off.
  • The portable jump devices have two clamps attached permanently to the tool.
  • These include one positive red clamp and another negative black clamp.
  • Try to keep them away to avoid any sparking.
  • Next, connect the red jumper cable clamp to the dead battery’s positive terminal and the black clamp to the ground or car’s chassis.
  • When you have made proper connections, switch on the power of the jump starter. Try to start the vehicle by turning the key to start.
  • Hold for a few seconds. If the car does not start, allow the battery to cool for a few seconds before you make another attempt.
  • Now try again. If your jump-start is working, your engine must start, let it run for a few seconds, and it will charge the battery automatically.
  • Now, disconnect the jump starter cables.
  • First, disconnect the negative black cable from the car and remove the red cable from the car’s battery terminal. 
  • If your engine does not turn over even after trying a couple of times, you may have another problem at hand; let an experienced mechanic take a look at your car and find the real reason. 
Jump start a car with portable jump starters

Jump start a car with portable jump starters

Choose jumper cables by vehicle type.

It doesn’t matter if you have enough knowledge about jumper cables.

The following can still help you get one.

Booster Cable Assembly: Compact

You can start a compact car with a 6-gauge jumper cable.

So, if you have a Kia forte or Mazda 3, you will need a 10 feet gauge-6 cable that can give 200 amps of current.

However, we suggest you still use a gauge-4 cable 20 feet long.

Also, look for the cable that can provide 400 amps for safe and best results.

Booster Cable Assembly: Sports cars

For fast sports cars, a 4-gauge 10 feet cable won’t do the work.

You will at least need a 2-gauge 20-foot-long jumper cable.

Although 400 amps are okay for sports cars, it would be good to choose 600 amps.

Also, pick the jumper cables having clamps of solid copper for a safe and secure connection. 

Booster Cable Assembly: Intermediate

For intermediate cars like Toyota Camry or Kia K5, you need a 6-gauge 10-foot jumper cable that provides 200 amps.

However, to ensure uninterrupted performance, you must go for a gauge 4 20 feet jumper cable supplying 400 amps.

Booster Cable Assembly: Full-size

For full-size sedans, you need a minimum of gauge-6 10 feet jumper cable, which can supply 200 amps of power.

For maximum performance, choose a jumper cable that is 4 gauge 20 feet long.

It will be much better if the cable can provide 800 amps of power.

Booster Cable Assembly: SUV/minivan:

For SUVs like Honda Passport, you need extra power to jump start.

Choose a 4-gauge, 10 feet-long jumper cable supplying 400 amps of power.

You can also take a 2-gauge, 20-feet long jumper cable with 800 amps of power for better results.

Van/Truck:

If you own a full-size van like Chevy Express, you need a 4-gauge, 10 feet-long jumper cable with 400-amp power to get your ride back on the road.

Further, a 2-gauge, 20-feet long jumper cable supplying 800 amps of power is more reliable, and such cables do not create any problems while jump-starting large vehicles of this size.

Battery Jumper Cable Assembly Product Details

Battery Jumper Cable Assembly Product Details

Conclusion

People usually do not keep their jump starters charged; however, it is essential.

Otherwise, you will need another car to bring your dead battery back to life.

Nevertheless, you will surely need a pair of jumper cables.

Cloom suggests you get 4–6 gauge cables 20 feet or 6 meters long.

Ethernet Cable Colors: How Much Do They Matter?

Blue ethernet cables

Buying an ethernet cable is not as easy as it seems. It has many varieties based on its types, lengths, and colors.

This article will discuss ethernet cable colors and what matters while picking an ethernet cable.

Understanding Ethernet Cable Colors 

Ethernet cables come in different colors, like all other cables.

Commonly, you will see gray, yellow, white, orange, and blue colors in them.

One color is not better than the other, but the colors help you to identify the cable for its intended application. 

Let’s understand this with an example. In the Department of Defense, the government uses several colors for all the ethernet cables to classify them based on data transmitted through that cable.

Red cable for mid-level, blue cable for unclassified data, and yellow cable for some confidential data.

Colors help in cable management. Imagine that you have a business where you have a server or a server room.

It may have a particular color scheme, and organizing your cables according to that color scheme will make your network infrastructure more efficient.

In addition, the differently colored cables make identifying and troubleshooting problems easy.

LAN network ethernet cable. 

LAN network ethernet cable. 

Color code for Ethernet Cables

Although no industry codes exist for a particular color, the industry tries to maintain consistency in some colors.

Gray Ethernet Cable

Gray Ethernet cables indicate standard Ethernet connections in commercial and residential networks.

Green Ethernet Cable

This color generally classifies crossover connection through which you connect different devices or computers directly.

Yellow Ethernet Cable

Generally, technicians use yellow ethernet cables for power over internet connections.

The IEEE developed this standard to classify the cables that deliver 30W current at the port when used with twisted cable pair ethernet cables.

Blue Ethernet Cable

This color is for terminal server connections. You can connect multiple systems to the LAN network with a terminal server connection without using a modem or any other network interface. 

Colored ethernet cables

Colored ethernet cables

Do Ethernet cable colors matter?

There is no relation between ethernet cable color to its performance.

Cable vendors only give specific colors to the ethernet cables to understand their use and connection type and differentiate their connections from their competitors.

Colorful network cables 

Then what matters?

Since colors do not enhance performance, you should consider other characteristics that matter when looking for one.

Ethernet cable Cat

Here we will describe the performance and use of each cable type except cat3 and cat5, as they are slow and discontinued.

Cat5 and Cat5e: Here, the “e” indicates enhanced features.

You compare cat5 and cat5e; you will find no physical differences.

The only difference is that manufacturers have followed more stringent testing standards to eliminate crosstalk (unwanted transferring of signals between communication channels). 

Cat 5e Ethernet cables are the most used as they have low production costs and support high-speed signal transfer.

Cat6 And Cat6a:

Cat6 cables support higher bandwidths than cat 5 and 5e, so they come at a higher price.

So, you can choose foil or braided shields to protect the twisted wires inside the cable.  

In Cat 6a cable, the letter “a” stands for augmented.

These cables are one step better than Cat 6 cables, and support bandwidth doubles that of Cat 6 cables.

So, you can get high transmission speeds over long lengths.

Cat 6a cables have shields and sheathing that are thick enough to eliminate crosstalk. 

Cat 7 and Cat 7a: These cables support higher bandwidth (100Gbps at a range of 15 meters) and faster signal transmission.

Additionally, these shielded cables use a GigaGate45 connector that shows backward compatibility with RJ45 Ethernet ports.

Although the GigaGate45 connector is a proprietary component with backward compatibility, manufacturers still faced issues with the Cat 7 cable’s previous standards.

As a result, they avoid it and use cat 6a instead.

Similar to Cat 7, Cat 7a also has high specifications. It supports 40-gigabit ethernet connections up to 50 meters with some improvement.

However, it only supports a few networks and is expensive, so you must prefer it only in some exceptional cases.

Cat 8: These ethernet cables have the highest specifications as they support a max frequency of 2,000 MHz with a speed of 40Gbps at 30m.

As these cables are always shielded to support such high frequency. 

t 8 ethernet cables support two connectors; thus, you can only connect three cables with a total length of 30 meters. 

High specifications make them overkill for regular residential use.

So, the cable meets the newest IEEE standards, which makes it a good choice for future-proofing despite its high cost. 

Caption: Cat and performance

Ethernet connectors

Ethernet cables use special ethernet connectors with a unique design, as these connectors have eight pins that keep the cable locked into place.

Typically, you can call them an 8P8C connector.

However, there are several 8P8C connectors with differences, which put the ethernet cables into different categories.

RJ45:

RJ45 stands for Registered Jack 45, the standard form that almost all ethernet cables (Cat1-Cat 6 and Cat 8) use.

Based on the wires’ color and arrangement, you will find two variations in them.

Is the T568B standard (more common and popular) and the T568A standard (less common and less important)?

GG45: as mentioned before, these are specific connectors for Cat 7 cables, and these connectors have some additional connectors to give versatility in frequency.

T ough it has backward compatibility with the RJ45 connector, this new connector seemed unimportant, and thus Cat 8 cables resumed RJ45 connectors.

Ether CON RJ45: RJ45 connectors are very easy to use, but there is doubt about their durability as they have built-in plastic chips which break easily.

As a result, manufacturers developed a rugged version of RJ45 connectors.

You can use them in professional Audio/Video applications that need long-term durability.

Ethernet Cable shields

Based on the outer shielding, twisted wires in the Ethernet cables are divided into the following categories.

Unshielded twisted pairs or UTP: You will find no foil or intertwined protective cover in these twisted pairs.

These designs make the cable flexible and highly inexpensive.

However, UTP cables may not have excellent signal quality, and you may experience crosstalk.

Shielded twisted pair or STP: These ethernet cables have a robust, braided shield T is a shield comprising copper or any other conductive material.

As an s result of this shield, these cables deliver good signal quality with reduced noise.

Foiled Twisted pairs or FTP/SFTP: You will find a foil shield that covers the twisted wires inside these cables to boost connectivity, reduce noise and enhance signal strength.

Ethernet cable compatibility

The best part about ethernet cables is that you can interchange them.

However, you may face issues with old cables like Cat 5 related to the fast data transfer speed. 

You can easily insert a cat 5 cable into a router with the newest 10G Ethernet interface, but the cable will slow the data transfer speed.

You can also plug a Cat 7 cable into a long-standing router that does not support high speeds, but it will work fine.

Ethernet Cable length

The standard measurements are 0.5, 1, 1.5, 2, 5, 10, and 20 meters Y; you can get these cable lengths from almost every supplier.

If you want long ethernet cables, measurements up to 75 meters are available but are more expensive.

You can get a big ethernet cable reel if you want cables for a house or any other permanent wiring.

There are reeled up to 500 meters or more. 

Ethernet cable jacket rating

Depending on the location, different types of cable jackets are based on the material. 

CM-rated cables: Have ethernet cables run from your personal or office computers to the wall port?

These are CM-rated cables commonly known as patch cords.

These cables are available in a stranded form; thus, they are very flexible, so you can connect short runs to your PCs to server racks.

CMR-rated cables: In these CM-rated cables, R stands for the riser M only; these cables are used as riser cables rather than patch cables, i.e., these cables run through the top or bottom of the walls or basement to the upper floor. 

You can also use CMR cables for residential applications.

They have to undergo a burn test to prove their self-extinguishing nature, but these cables are less strict regarding fire requirements than CMP cables.

But they are more flexible, so if you use them at home for networking, it would be easier to arrange them.

CMP-rated cables: Here, the P stands for the plenum M style; you will find these cables in homes and offices if networking is done through ducts.

Ethernet connectors and socket 

Ethernet connectors and socket 

Conclusion

The color code of the outer plastic jacket in the Ethernet cable does not indicate anything.

However, engineers sometimes use colored cables in different zones in local area networks to understand each cable’s purpose.

Tough color does not matter; quality does.

If you want high-quality ethernet cables for your home or office networking, contact Cloom.

Aircraft Wire Harness: How the Air Industry Evolved with Time

Wire harness in aircraft

Electrical harnesses are a staple in modern electronics and the backbone of the auto industry.

Without it, the systems inside these machines wouldn’t be automatic.

However, technical progress has allowed the use of adaptable and robust wire harnesses useful in other complex industries, like the aerospace or aviation industry.

Let’s see how the aircraft wire harness evolved during the period and how they are used now.

Innovations in Aircraft Technology 

Flying in today’s high-tech world may seem like a mundane experience, something that most of us experienced before.

However, airplane technology has progressed a lot thanks to its rich history.

When planes first took to the skies, aerodynamics was the key to getting from point A to point B.

Thermal airships, or hot air balloons, were the first aircraft to carry humans.

However, aerodynamics and motor technology advancements in the early 20th century made powered-controlled flights increasingly common.

Similar to modern airplanes, these early models were developed by 1909.

Aerospace engineering has advanced through the years, with more potent aircraft engines and new improvements in aircraft wiring harnesses.

Aircraft and the aviation sector, as it exists now, would not exist without the technological breakthroughs it has experienced.

At the same time, an aircraft wire harness serves the same primary function as any other wiring system and the innovations it has brought to the aerospace industry.

Caption: Hydraulic lines inside the aviation system

Why Do Aircraft Have Wiring Harnesses?

There was no such thing as a wiring harness in the early days of airplane development since electrical systems did not exist.

They had to move the flying control surfaces using only structural parts, ropes, and pulleys.

Metal cables soon replaced the ropes; even today, many planes don’t “fly by wire,” instead relying on cables and pulleys.

Eventually, an airplane designer decided to wire in a light and put in a switch, battery, and bulb.

He connected these parts with cables, creating the airplane’s first electrical lighting system.

Since this system only required a small number of wires, harness manufacturers put them individually in safe locations.

Subsequently, other architects came along and incorporated even more electrical infrastructures.

Aircraft mechanics eventually realized that they were installing cables one at a time despite groups of wires flowing from one part to another.

Moreover, they needed more wires for each additional device.

The duration of this setup process was lengthy.

Mechanics began grouping and routing cables together in bundles to increase productivity.

The aviation industry took notice and deemed this a worthwhile development.

After conceptualizing the wire bundles as a whole, they assembled them there.

With this, they created the first wire harness.

Aircraft wire harnesses serve this purpose.

Shot wire tubes inside the wall

Caption: Shot wire tubes inside the wall

The Functionality of an Aircraft Wiring Harness

Similar to how a car’s harness directs electrical impulses, a plane’s wiring harness does the same for the complete aircraft.

The engine, landing gear, wings, and fuselage are only some of the functions it regulates.

Wire harnesses typically have a great deal going on inside of them.

Miles of cables, wires, and thousands of individual parts make up an airplane wiring harness.

In addition, they all have to function together to keep the plane flying smoothly.

Today’s aircraft manufacturers must also keep up with rapidly developing technologies and upgraded aircraft wiring connections to support cutting-edge additions.

In addition to improving efficiency in production and manufacturing, an aircraft wire harness also makes it easier for mechanics to identify and repair planes experiencing technical difficulties.

Wire harnesses eliminate the need to install the electronic systems of a humongous plane separately.

When problems arise and maintenance is required, mechanics must identify the affected component to fix it.

Three Categories of Parts in an Aircraft Wiring Harness

The aircraft you will put it in is a significant factor in determining the specific elements and components of the wiring harness when designing a plane that meets military specifications; there are many things that you have to take into account.

These are the three types of airplane components.

Standard Components

In a plane’s electrical system, the military will often have the final say over the components known as MIL-SPEC (military standard).

The letters M or MS appended to the beginning of the serial number designate them as a military issue.

Some are prefixed with the letters NAS to show that they conform to the National Aerospace Standard.

A few standard component prefixes exist, but these two are the most prevalent in a military plane’s wiring harness.

On the other hand, the military and many other aerospace sectors.

Nonetheless, the government must certify specific manufacturers before you can consider them as authorized suppliers.

Non-Standard Components

Non-standard components are frequently variants of commercially available components that meet a slightly different military standard.

Original equipment manufacturers can dictate the criteria for non-standard components (OEM).

Original Equipment Manufacturers also have the option to permit which of their suppliers to produce non-standard components.

However, the cost of a non-standard element for an airplane harness tends to be higher since so few exist.

Commercial, Off-the-Shelf Components (COTS)

Manufacturers mass-produce COTS components in response to market research and consumer demand.

The producer can improve the design of the components without permission from the government or the defense.

A manufacturer can create their parts and assign them unique part numbers.

As with the other two components, you can purchase COTS options from vendors at a reduced cost.

However, manufacturers have exclusive power over the distribution of COTS components, allowing them to set prices and determine market share.

Furthermore, they have the freedom to alter or amend any requirements.

However, it might cause a problem as it becomes essential to source new components for a plane’s wiring harness due to a depleted supply.

Aircraft Wiring and Connection

Aircraft wire harnesses have wiring that is miles long.

Therefore, you need to plan and structure them precisely to prevent problems during and after construction.

Thus, the first step in any design process is the creation of a schematic in CAD software. It serves as a guide for subsequent construction.

Insulating materials used to be a one-size-fits-all affair, but nowadays, many options are available to meet various needs.

The signal you send, and the system’s electricity dictate which wires are used. Wire insulation also shifts with these variables.

It would also help to label the wires so that assembly and repairs don’t mix them up.

However, when picking a connector, you should remember these three things.

The number of connections that the connector can accept should come first.

The second factor is the thickness of each wire, and the last is the type of wire to enter the aircraft connector.

Conclusion

The aircraft wire harness is based on different wires and connectors.

Moreover, other standards, non-standard, and COTS parts make the harness complete and functioning.

While choosing the elements, you need to look into your requirements.

Then you will get to design the schematic using CAD software.

At Cloom, we offer wiring harnesses and cable assemblies to make your connection safe and reliable.

How To Wire A Harness: An Ultimate Guide on Automotive Harness Wiring

How To Wire A Harness

How To Wire A Harness?

When you get a factory harness for your vehicle, you will get all the wiring essential for all the standard electrical components such as headlights, horns, windshield wipers, etc.

However, you sometimes want to add more electrical components to your vehicles, such as racing electronics or high-end audio.

If you want your systems to work at their full potential, you need to learn a few tips related to making the wiring of a harness easier and more effective.

Round up the right tools

The wiring job becomes much more manageable if you pick the right tools. 

First of all, take good quality wire strippers. Mostly, wire strippers have several holes that can fit different wire gauges.

The wire strippers help strip the insulation off the wires properly without damaging the conductors inside. 

The second tool that you may require is a wire crimper. You can install solderless connectors with a wire crimper.

If you choose a quality crimper, it will have two-three sections on its nose to fit into various lug sizes.

Additionally, there are crimpers with wire cutting and wire stripping sections. 

Some connectors are difficult to crimp; thus, you need a soldering iron to splice and secure such oversized connectors.

Several solder types are designed specifically for electronic products and electric wiring.

They have active resin core flux, which cleans the wires on heating.

As a result, it removes any extra oxidation or corrosion on the wires.

When cleaned, you can solder the wires with lesser heat, making the connections strong and having less electrical resistance. 

Other than these basic tools, you should also have these items in your electrical toolbox:

  • A wire brush so that you can remove grease, oil, or heavy corrosion before soldering.
  • A voltmeter and an ohmmeter measure the circuits’ voltage and resistance levels.
  • A test light with which you can check the power in the circuit.
  • Shrink tubing materials for insulating connections from outer elements. You can insert this tube over the connector or the solder joint, which shrinks permanently on heating. 
soldering iron

soldering iron

Gauge your wiring needs

While choosing wires for electrical systems, you must consider three essential factors.

Size: You measure the wire size with its gauge. As the gauge becomes heavier, the wire becomes smaller, and vice versa.

Now, how will you decide on the wire gauge? You can choose it based on the current drawn in the accessory and the length of the wire between the power source and the accessory.

If the current in the accessory is high, you must take heavier gauge wires.

Caption: Wire Gauge to Wire Diameter Comparison Chart

However, when the wire is of longer lengths, you may face the issue of voltage drop.

But you can offset this drop by increasing its size. As a thumb rule, you should try to get less than a .5% of voltage drop to ensure the highest performance.

Wire materials: Generally, the wires are made from aluminum or copper. If you choose wires for automotive applications, you must take copper wire for higher flexibility and conductivity. 

Wire color: It becomes essential when you have to find out about any faulty wire.

Thus, it is always better to color-code all the wires based on the accessory.

Such marking will help you identify wires during installation and troubleshooting. 

Make the connection

You can take either of the two connectors: soldered and solderless. 

You will need soldered connectors for oversized wiring or splicing the wires together. 

On the other hand, all other wires use solderless or crimp connectors. Solderless connectors are very easy to use and give a powerful connection.

These connectors come with color-coded insulators so that you can know which one to use for which gauge wire.

You can get various configurations in solderless connectors as follows:

  • Butt connectors: These cylindrical connectors are ideal for joining the ends of two wires together. You can insert each wire end into each end of the connector. After inserting, crimp the connection to secure it tightly.
  • Spade connectors: You must use this type of connector for all those components requiring removal or servicing quite often. Here, you connect the male connector at one end of the wire and the female at another. This male and female connector will fit into each other to form the connection. When you want any repairs, you need to pull the wires apart.
  • Ring connectors: You can fix the wires to screw-type terminals with these connectors and secure them with a terminal screw.

Whether you are using soldered or solderless connectors, it is always advisable to use heat shrink tubing to make the connection more secure and safe.

Heat shrink tubing is easy to install and protects against short circuits and other outside components.

Insulated female electrical wire crimps terminal connector.

Insulated female electrical wire crimps terminal connector.

Choose the correct wiring harness components.

When wiring a harness, you should take some overload protection to save your expensive electronics from getting damaged.

There are three main types.

How To Wire A Harness: Fuses

You can connect a fuse to a circuit.

Whenever more power is in a circuit than required, the fuse will blow, thus protecting the circuit from shorts. The fuses come in amperage ratings; the most common ratings are 3,4,5,6,7.5, 10, 12.5, 15, 20, 25, and 30 amperes.

It is advisable to use a fuse slightly higher than the rating of the accessory.

For example, if an electric fan has a rating of 19.5 amps, use a fuse of 25 amps.

How To Wire A Harness: Fusible links

Fusible links are another way of protecting the circuits.

These alloy-made wires have a melting point lower than regular copper wires.

You can splice the link in line with the accessory’s power line.

When there is electrical overloading, this link will melt and thus prevent the electrical power from reaching the accessory.

How To Wire A Harness: Circuit Breakers

The circuit breakers switch off the power to the electronic accessory whenever there is an electrical overload.

Once you restore the correct power, you can reset the circuit breaker.

There are circuit breakers with manual as well as automatic reset options.

They all come in different amperage ratings as fuses.

How To Wire A Harness: Relays

You can also use relays in the wiring of the electrical accessory if they draw higher currents than standard power rates.

As most switches have designs to work with limited currents, you need relays whenever you buy a new electrical accessory from the market.

Relays become more critical when using electrical accessories with high amperes, such as fuel pumps, electric fans, HID headlights, etc.

These accessories activate with an electrical coil and get controlled by a switch.

No power flows to the accessory if the relay is in a close position.

When you turn on the accessory switch, the relay opens and sends power to the concerned accessory.

Apart from these, several other components make your wiring easier, such as 

  • switch panels, 
  • push-button, 
  • toggle, 
  • remote-mount switches, 
  • multi-circuit main and auxiliary fuse blocks, 
  • and wiring harnesses.
How a relay works

How a relay works

Map out a plan

It would help if you always mapped out a plan before you started your wiring project. 

First, lay out the wiring and harnesses to understand the basic wiring scheme and whether you have enough wires to complete the task.

Put the fuse box in an easy-to-reach location, such as in the glove compartment or the center console. 

Now, put all the required relays, circuit breakers, fuses, and fusible links at the wiring connections between your electrical accessory and the power source. 

See if the wiring is labeled.

If not, label all the wires and harnesses according to the name of the electrical components they are routing to.

If any wire goes through the firewall, use a grommet so that sheet metal does not cut the wires.

Secure the connectors only when the wiring has been done through the firewall.

Pick a spot near or on the firewall for the cable harness’s ground point and another point for the chassis ground on the vehicle’s negative side.

With this, you get one path to the negative side of the vehicle and provide a more effective ground point.

Always use a gauge wire of 10 or more to connect the chassis ground to the common ground. 

Keep calm, stay organized, and take sufficient time to understand and manage things to complete harness wiring.

If wiring is done correctly, the installation time of the wire harness assembly process decreases rapidly.

Lay out the wiring harness

Lay out the wiring harness

Conclusion

Complex wiring is like a nervous system for your vehicle.

If not done correctly, one or more electrical accessories may stop working overtime. If you need any support, Cloom technicians are here to help you.

Our knowledgeable and expert team of engineers and technicians can guide you through the entire process.

Also, we manufacture high-quality custom wiring harnesses and cable assemblies for various application requirements. 

Voltage Imbalance: How to Deal With This Power System Fault

Voltage Imbalance

In industrial plants, electrical power issues are pretty common. Current harmonics, voltage unbalance, and current unbalance some of them. 

These issues lead to abnormal functioning of the electric power systems.

Of all of them, the unbalanced voltage condition is the most hazardous.

Let’s learn about voltage imbalance issues and how to prevent them.

What Is Voltage Imbalance?

There is no particular definition of voltage imbalance, it is simply the voltage difference between different phases. 

Generally, in three-phase motors or polyphase systems, the voltage between different phases should be equal or nearly equal.

However, due to some issues, three-phase voltages become unequal, resulting in negative or zero sequence currents.

Major Effects of Voltage Imbalance

Sometimes, there are extensive voltage imbalances.

As a result, it impacts polyphase motors and other electrical loads. 

Unbalanced voltage mainly causes motor failure due to extreme heat.

Because the voltage unbalances produce high unbalance currents, these currents produce heat and increase the winding temperature.

As a result, it can damage motor insulation. 

Also, a severe imbalance in voltage can lead to the overheating of components in the motor, and there can be severe or permanent damage to the motor.

Motor failures, in turn, lead to user facility downtime.

Voltage imbalance also creates negative sequence voltage, and this negative voltage produces opposite torque.

As a result, there is vibration and noise in the motor. 

Sometimes, imbalances in power systems also lead to transformer failure, and relay malfunction is also one of its adverse effects.

motor winding

Image: motor winding

Causes and Sources

Several factors affect voltage imbalance in a distribution line, which is either general or motor-related.

General:

  • Unequal distribution of single-phase loads
  • Overloading in feeders due to electrical faults
  • Faulty equipment
  • Unbalanced power source voltage

Motor:

  • Wrong tapping in the transformer
  • Unbalanced load in three phases
  • An Unequal impedance of the three-phase distribution system
  • Unbalanced loading of capacitors
overload

Image: overload

Voltage unbalance standards

Specific standards decide the limit of voltage unbalance, and ANSI recommends a 3 percent unbalance in voltage for electrical systems.

You must take this percentage under no-load conditions.

However, according to Pacific Gas and Electric, this voltage imbalance percentage should not exceed 2.5.

According to NEMA MG-1-1998, there is just a 1 percent unbalance limit, and this rule is the strictest.

NEMA is an association that represents motor manufacturers.

Per the NEMA rule of 1% voltage imbalance, a current unbalance 6-10%.

On the other hand, some makers fix the current imbalance value to less than 5%.

It is essential to get a valid warranty, which means the makers’ requirements are stricter than NEMA MG-1.

At times, disputes arise between customers and makers due to this difference.

Thus, you need to check the service guidelines of the utility at a specific location.

Testing for Voltage Unbalance

To test the voltage unbalance, you must measure phase-to-phase voltage.

The 3-phase system has a connection across phases.

Thus, do not measure phase-to-neutral voltages.

Take the phase-to-phase voltage readings with a voltmeter. 

According to IEEE, it is a ratio of the positive and negative sequence components.

Now, use this formula to calculate the percentage of voltage unbalance.

Voltage unbalance percent = 100* (maximum voltage deviation/average voltage)

The average voltage is the average of voltages across all three phases. 

This formula identifies the unbalanced voltage magnitude present in the system.

If there is any, you must determine the problem source.

The unbalanced situation can be due to the motor or the power.

Follow these steps to know the source of unbalance:

  • Firstly, measure and note down the current through each load
  • Secondly, rotate all power lines (three) by one position. However, please do not change the order; it will change the motor’s rotation.
  • Now, again measure the current across all leads in this new position.
  • Now, again rotate all power lines by one more position.
  • Again, record the current across all lines in the new position
  • For every three rotations, calculate the average value of the current. Observe the power line/motor lead combination that shows the maximum deviation from the average current.
  • Finally, compare all three power lines with the most current deviations. If the combination always has the same motor lead, the problem is with the motor. On the other hand, the same power line in combination indicates a problem with the power supply.
electrician testing industrial machine

Image: electrician testing industrial machine

Voltage Unbalance Mitigation

The issues of power quality are obvious in distribution networks.

You cannot make voltage imbalance as Zero in a distribution system because of three reasons:

  • Firstly, the connection and termination of single-phase loads are random
  • Secondly, due to the uneven distribution of loads in the three-phase system
  • Finally, due to the asymmetry of the power system

However, you can mitigate it after a thorough voltage imbalance study.

To reduce the effects of voltage unbalance, you can use the following:

Utility level methods.

  • Redistribute single-phase loads across all phases.
  • Reduce unequal impedance due to transformers and lines
  • Decrease single-phase regulators to correct the imbalance. However, you must use them carefully.
  • Use active and passive electronic systems to correct voltage imbalances.

Plant-level methods:

  • Do load balance?
  • Avoid connecting sensitive equipment to systems with single-phase loads
  • Make sure that you size the AC side and DC link reactors properly.
  • It reduces the effect of voltage imbalance in speed drives.
  • Have passive networks.

Conclusion

The impacts of Voltage imbalance are harmful to motors.

Thus, you must adequately find and correct the problem.

When you balance voltage, the life cycle of equipment becomes better.

As a result, you save time, energy, and maintenance costs.

Thus, it would be best if you properly tested the electrical equipment.

We can help you in managing your electrical systems.

We deal in premium quality cable assemblies.

Live Testing: How to Do It While Avoiding any Health Risks and Problems

An electrician checking an industrial machine

There are two things you want in your facility.

First, you need the gear to deliver optimal and consistent performance. Additionally, the equipment shouldn’t cause any damage or accidents, with injuries. 

Live testing can help to maintain both goals. It involves checking if the gear works right while it’s operating. 

But, there is something you should know before working near or around the energized equipment.

What Does Live Testing Mean?

Caption: An electrician working on maintaining electrical equipment

If you handle electric testing sessions, you should turn off the power supply to the gear.

The experts recommend deactivating it for personnel safety.

The problem is that you can’t test a device’s performance without checking how it works.

Live testing involves checking the system while the power supply is active.

It helps in finding faults, but it also carries more significant risks.

Therefore, you should ensure trained electricians handle the action.

The experts suggest that live testing is possible on all gear and conductors that work at no less than 50 volts.

The Electricity at Work Regulations suggests when live testing should occur:

  • If the device vitals need to remain “live” at all times.
  • The electrician can do the checks while the device is “live.”
  • If you take all precautions to maintain safety and prevent injuries.

Tests That We Carry Out “live”

The device list is up to you to decide.

As for the series of tests to take, here are the ones that the experts recommend.

Polarity Tests

This test involves circuit breakers, switches, and fuses.

In other words, these are single-pole devices connected to the PHASE conductor.

The idea is to confirm the relationships are optimal.

That way, we ensure the electricians did the setup right. It minimizes the damage risk for the entire apparatus.

And you’ll only need a plug-in tester. You’ll read the numbers on the charts to confirm the correct polarity.

Earth Loop Impedance Test

Let’s assume that a fault occurred in the electrical system.

The circuit breaker or fuse should get enough current flow to protect the faulty circuit.

It ensures the earth cable resistance is low enough to continue operating correctly.

You do loop tests to see if the circuit disconnects on time to keep a fire or overheating from happening.

You can use no-trip testing with three wires.

Label testing involves connecting these to earth, neutral, and live conductors.

Make sure the test current isn’t higher than 15mA.

The process won’t trip MCBs; you don’t have to go around RCBOs and RCD.

That ensures you save time with this test.

Prospective Short Circuit Test

Technician testing a control panel

Caption: Technician testing a control panel

If this fault happens, the cable should handle enough current to blow a fuse or trip the MCB.

The guidelines indicate this should happen within five seconds for fixed gear. However, the time reduces to 0.4 seconds for any portable equipment.

The prospective short circuit test ensures the cable handles the fault as expected.

During this test, you check the current in live conductors when a fault occurs.

It’s necessary to check Line to Neutral and Line to Line in three-phase setups.

For single-phase installations, check Line and Neutral. Furthermore, write down the result in hundreds of amps.

Residual Current Device Test

If an electrical fault occurs, there should be a safe RCD “tripping.”

You will trip it on purpose during this test.

That way, you confirm it works quickly if a fault happens.

The RCD will turn off all the channels where the circuit receives power if it doesn’t trip.

The residual current device test is vital to keep electrocution incidents.

Here is how to do it:

  1. First, connect the equipment and adjust the desired RCD rating. The test starts with half of the rated tripping current of the device.
  2. If the RCD doesn’t trip, increase the rated tripping current. The average time to trip out is 0.3s.
  3. Increase the test rating to 5x the rated current. You should note that the RCD takes less time to trip than in the previous step. The change will only be minimal.

Electrical Lnjury Risks When Fault Finding and Testing on Energized Equipment

The problem with live testing is that it includes significant health hazards.

After the device selection, minimize the risks of potential issues.

Here are the problems that might happen!

Electrical Shock

An illustration of an electrical shock

Caption: An illustration of an electrical shock

If the electricity goes through your body, you have an electric shock.

The consequences might be dangerous and even fatal.

Electric shocks can cause severe burns on the surface and inside your body.

They can lead to a fall because they make you lose your balance.

It’s also possible a shock starts to come into contact with a conductor with a higher voltage.

You might also have problems making any movements, or your movements might be involuntary.

Electrocution

This term also refers to an electric shock.

However, electrocution describes a severe injury or fatal consequences of the shock.

The health risk depends on various factors and not only the voltage.

You must also assess how much current goes through the body and for how long.

Your breathing can stop if a current of as little as 30mA (1 amp) goes through your organism.

Winds over 1A can cause permanent damage to cells and burns.

A standard 125V circuit in households can send 15 amps of current to your body.

Therefore, it’s hazardous, and caution is necessary when dealing with electricity. 

Arc Flash

A spark explosion

Caption: A spark explosion

A significant electrical explosion happens when an arc fault happens.

The first byproduct of that event is an arc flash.

That includes heat and light that come from the blast.

Caption: how arc flash looks

If we are talking about the temperature, it can go up to 19,000C, and the usual range is about 3,000C.

As a comparison, the Sun has a temperature of 5,000C on its surface.

The heat from the arc flash can burn your clothing, skin, and even internal organ damage.

Therefore, it could have serious consequences.

Arc Blast

Apart from the flash, the explosion will create an arc blast, a pressure wave around the device that explodes.

The shots are strong and can throw you on the other side of the room.

Furthermore, they are loud, so you could deal with hearing damage.

Even your brain functions are in danger.

It’s not only the people who the blast can throw around.

The product can throw machinery and tools around, hurting you.

Burn Injuries

The dangers above can involve burn injuries.

So, they are a significant health hazard to the electricians and people in the facility.

The burn degree can vary depending on how close you are to the arc flash.

Some burns might be superficial, but others can be dangerous and even fatal.

What Can You Do to Minimize Health and Safety Risks?

The actual regulations depend on your location.

However, here is what you should consider when testing public devices.

Assess the Risks First

 Risk assessment illustration

Caption: Risk assessment illustration

What can go wrong during the live or “near-live” testing?

You should hire a qualified person to assess the risks.

Apart from the arc flash and direct electric shock, you should consider conductive materials, and these have paths that the prospective fault current can follow to cause a shock.

Here is how risk assessment works:

  1. A qualified staff member should assess the current situation. That involves finding potential electrical and other risks during the test. Make sure it’s comprehensive coverage of potential hazards.
  2. The testing should comply with any laws and regulations.
  3. There should be a risk assessment report in writing.
  4. The report should contain suggestions on how to manage the risks.

Don’t Forget the SWMS

This is short for a Safe Work Method Statement, and the regulations require it.

You need a qualified person to write it; this report can include the actual risk assessment.

Here is how writing SWMS works:

  1. Talk with any relevant workers to find potential risks.
  2. Discuss which work is a part of the plan for the test.
  3. What measures can help to manage the risks? It should include additional info on each risk control action. Additionally, it should review if the relevant staff takes that action.

The person doing the test should be aware of the SWMS.

If you change any work or safety procedures, you might need to change this document, too.

Use Personnel with Adequate Training

It’s needless to say that a professional should do real-time testing.

They should understand how devices work and know how to use relevant instruments.

Furthermore, they should also be aware of safety issues.

Knowing how to act to minimize risks is vital for safety, and it ensures that the ongoing testing efforts and the process go smoothly.

The Importance of the Protective Gear

Industry experts call this personal protective equipment (PPE).

It’s vital to adjust it to the needs of the individual tests.

Here is what protective equipment staff should use:

  • Face. The individual should wear a full shield in case of an arc flash. Check the availability status of the shield before beginning the test. Additionally, don’t wear spectacles with metal frames.
  • Gloves. What voltage do you expect? The authentication options should only include gloves that can handle the expected voltage.
  • Clothing. The highest thermal rating with flame-resistant materials is the smart move. You don’t want to wear synthetic or flammable material.
  • Footwear. Your shoes might be conductors. Make sure they aren’t before you enter the pre-production test environment.

Safety Barriers, Signs, and Observers

A warning sign

Caption: A warning sign

A safety barrier helps avoid contact with a dangerous part of the electrical setup.

You’ll need to assess whether these barriers are necessary for individual tests.

There shouldn’t be issues with an unauthorized request because safety is everyone’s top priority.

You can use plastic, wood, or another non-conductive material for the barrier.

Make sure the border won’t fall if you accidentally hit it.

It’s the minimum version of sturdiness it should have. 

It would help if you had safety signs, too.

These are warnings to people who might enter the test area, and you can avoid a civilian disrupting the ongoing testing efforts and potentially suffering injuries.

The regulations also recommend a safety observer.

For each piece in the device list, they monitor optimal risk management on the spot.

If an emergency occurs, the observer should act to minimize the risk.

Knowing the facility and device details can help with that. 

The observer should talk to the staff member doing the test.

And forget about mobile devices because communications need to be direct and effective.

Work Completion

If you deactivate the power supply, don’t rush with energizing the devices.

Here is what you need to confirm first:

  1. Check if you removed any waste or private devices you used during the individual tests.
  2. Place covers and guards back in their places.
  3. Make sure to remove and note any temporary earthing equipment or electrical bonding.
  4. You must warn employees that you have finished unit tests and plan to turn the power on.

What If You Don’t Finish the Work?

A single day might not be enough for the entire assembly of tests.

If that happens, you can leave the unit tests for another time. However, make sure that the place remains safe.

The safety actions when postponing application testing include:

  • Shroud or terminate exposed conductors.
  • Furthermore, it would be best if you physically secured them.
  • Make sure to place warning signs about the tests on any device windows you plan to check
  • Put additional information panels for other employees to avoid potentially risky areas.
  • Make sure you inform the workers about the current index status. That way, you ensure they can continue to work safely.

Use Approved Equipment

Here is another crucial safety point.

If you want to test an actual device, use only approved equipment to ensure accurate testing results and show precise device vitals.

If you don’t have adequate equipment, don’t use an alternate version, which increases the risk of something going wrong.

Make a careful device selection and use only proven instruments during testing.

Electrical equipment

Caption: Electrical equipment

Conclusion

There are situations when only live tests can give more info on the device’s vitals.

If you plan to test equipment while the power supply is active, consider safety a top priority.

You can protect everyone involved in the approved ongoing testing efforts.

And if you need help with electrical wiring, don’t hesitate to contact Cloom.

We have years of experience and can meet any requests your facility needs!

Harmonic Study: The Guide to When, Why, and How to Do This Analysis

A waveform illustration

Harmonic currents and voltages can harmonic currents and voltages can have various strengths.

Depending on the electrical setup, the system can handle those levels.

A harmonic study helps you analyze this wave distortion and reveals whether its ranges are acceptable.

That allows you to find potential issues and deal with them.

If you’d like to learn more about harmonic study, we have a detailed guide below!

The Overview of a Harmonic

Harmonic is a type of waveform that occurs in electricity.

The form is non-sinusoidal and occurs periodically. So, how would you present it?

 Sine wave - illustration

Caption: Sine wave – illustration

You would use a sum of the sine wave whose integer is the basic frequency’s multiple.

However, there might be a superposition between the harmonic wave and the basic frequency.

If that occurs, you’ll notice the forming of a distorted wave, and that’s what makes it non-sinusoidal.

How to Produce Harmonics

You need a non-linear load to produce harmonic waves.

That’s because a non-linear load reduces the amount of electrical energy the system utilizes.

So, these loads imply semiconductor components achieve higher efficiency.

While that’s useful, these parts can lead to interference.

That interference appears as current distortion. It also adjusts the voltage signals that go back into the power setup.

If that happens, that means a harmonic occurred.

Here are the most common harmonic sources across various industries.

Electric Devices

A PC desktop can cause harmonic waves

Caption: A PC desktop can cause harmonic waves

A wide range of products can cause harmonic distortions.

That includes the following: 

  • Pumps and fans that have VFDs – variable frequency drives.
  • Personal computers and instruments with SMPS – a switched-mode electricity supply.
  • Harmonic distortion can appear in systems for battery charging.
  • You might face this waveform if you have a flexible AC transmission system.
  • VAR compensators that are static and non-interruptive power supplies can also have harmonics.

Magnetic Gear

The condition is that the equipment is saturable.

For example, this gear can lead to harmonics:

  • Harmonic generators. Synchronous generators create them because the air gap has a flux that distributes in a non-sinusoidal form. You can pick a pitch factor to decrease the harmonics.
  • Transformers. If overexcitement occurs, it might lead to harmonics. If an inrush current occurs, you might notice some waves. However, they only last for a short while.
  • Discharge lamps. Fluorescent lamps and sodium at high pressures can lead to harmonic currents.
  • Rotating machines. Third harmonic currents can appear from induction motors. However, these machines must be under non-standard conditions.

An Analysis of Harmonics’ Effects

A warning sign with graphics

Caption: A warning sign with graphics

Harmonic voltage distortion can cause a wide range of issues.

It has various effects on different parts, including:

  • Capacitors. You’ll find the capacitors and the system has a parallel resonance. That could lead to a shorter conductor lifespan and even its destruction.
  • Conductors. The resistance and current might increase, which leads to cable heating.
  • Neutral conductors. The current can return via these parts. Therefore, you could face overcurrent, heating, and a shorter lifespan of the conductor.
  • Transformers. You might notice too much heat because the harmonics go via windings. Furthermore, that leads to losing thermal insulation and affects overall performance. The torque could be lower, and bearings will deter quickly.
  • Motors. The performance might suffer, and you could face similar issues as in Transformers.
  • Control devices. You can get wrong results and errors. That refers to magnitude values and the zero reference of a wave.

When a Harmonic Study Is Necessary

A person writing down the factors when a harmonic study is necessary

Caption: A person writing down the factors when a harmonic study is necessary

If you are unsure when to do a harmonic study, here are a few pointers:

  • Did you notice a large quantity of non-linear loads? Do a harmonic study if they are above a fourth of the systems or bus’s total load.
  • Is there an issue with power quality?
  • Do the parts of your power system deal with damage frequently?

These are all good reasons for harmonic analysis. You can also do it to meet regulations and check the system’s performance.

What Are the Goals of a Harmonic Study?

Waves oscillating - illustration

Caption: Waves oscillating – illustration

Your goal might depend on the industry. However, the common tasks include:

  • Meeting the Standard 519 of The Institute of Electrical and Electronics Engineers. It’s a document that refers to harmonic control in electric systems.
  • Check how the harmonic distortion affects the system.
  • Suppose you plan to add non-linear loads to expand the system. The harmonic analysis can help to learn how to improve the setup to suit the new needs.
  • Suppose you notice problems that harmonics can cause. Those could include overhearing, devices not working well, etc.
  • That’s part of planning an entirely new power setup.

What Do You Get with a Harmonic Study?

An electrician reading the power output

Caption: An electrician reading the power output

Why would you analyze harmonic generation?

There are many reasons to do a study.

  • Check the existing power setup and collect important data. You can use this data for other tests later.
  • Find where high-harmonic generation appears in your system. Furthermore, learn about its type, place, and size.
  • Check how harmonic conditions affect current and voltage in your setup.
  • If there are any harmonic penetrations, you can learn about them.
  • Find the THD – total harmonic distortion – and its magnitude on each frequency.
  • You’ll learn if the distortion levels align with relevant codes and requirements.
  • Measuring any harmonic indices to ensure they meet the standard is possible.
  • Find if there is any serial or parallel resonance.
  • If you need them, you can create and check harmonic filters.

Harmonic Study and Analysis – Details on How to Perform It

The IEEE developed a guideline when doing harmonic analysis studies.

You can check it to learn more about the process. Here are the major things you should know!

What Tools Do You Need?

Various electrical equipment shown in the photo

Caption: Various electrical equipment shown in the photo

Before you start, you should have the right tools.

If you have a small system, you can go for manual calculations.

However, please note these can lead to errors.

Furthermore, they are often complex. 

You can also try field measurements.

They are useful if you need to check the design or if there is a field issue. If the latter occurs, it can help you diagnose it.

The most common way is a computer simulation.

It’s affordable and simple, but it gives accurate harmonic analysis.

What Data Should You Acquire?

To do a harmonic study, you must get various data first.

Here is what you should have:

  • Gather the system details.
  • The nominal voltage of your bus and limits of harmonic distortions.
  • If there are non-linear loads, what’s the maximum voltage you expect?
  • The short-circuit MVA for the single and three-phase setups. You also need zero, negative, positive, reactance, and resistance sequences (if applicable).
  • Use the basic frequency to get rated voltage, kVa/MVA, and negative reactance. Do this for both the generators and the motors.
  • You’ll need kV ratings of any shunt reactors and capacitors.
  • Resistance and reactance of circuit elements, such as the bus duct and reactors that limit current.
  • The number of pulses, phases, converter connections, and nameplate ratings.
  • The structure and type of the harmonic filter. If there are special buses, make sure to get harmonic limits for each.

Collecting and Preparing Data

An integral step in harmonic analysis is to prepare and model data. It will depend on the system device, but here are some tips:

  • If there is power grid data, ensure the utility is the source.
  • For load data, get it from any tests and the load nameplate.
  • Include test information along with the data from the designer for cable and line data.
  • The manufacturer will deliver data on the rotating machines. Use that info, and details from the factory acceptance test and other checks.
  • Get the info on the transformer and other parts from the nameplate.
  • The manufacturer should get you info on non-linear unit voltage-current features. The same applies to the harmonic filter and current and voltage harmonic spectrum.

If you performed any tests in the above areas, show that data, too.

Step-by-Step Instructions

An illustration of a checklist with the completed first step

Caption: An illustration of a checklist with the completed first step

Do you want to conduct a harmonic study?

The steps are similar for commercial and industrial facilities.

Here are the actions to follow:

  1. You should have a single-line diagram.
  2. Make sure you have the ratings and other info on the gear.
  3. Check where non-linear loads and harmonics appear. Make sure to write down the places.
  4. Call the utility provider and get the PCC’s data and harmonic specifics. Get the lowest and highest fault limits or system impedance that acts as a frequency function in various system conditions. Additionally, get acceptable levels for harmonic distortion.
  5. Analyze the default configuration. You need to find the shunt capacitors and harmonic source bases and find the driving point impedance loci.
  6. Find the total harmonic voltage, as well as the individual one.
  7. Check the ratings with the ones that standards suggest.
  8. If you find something to go above the normal level, make sure to adjust the capacitors.
  9. You’ll need filters in areas where harmonic distortion exceeds the acceptable range.

For the seventh step, here is more information on the adequate ranges:

  • The current should be less or equal to 180% of the rated RMS.
  • KVAR should be less or equal to 135% to its ratings.
  • RMS crest voltage can be less or equal to 1.2 times the rated level.
  • The continuous operating voltage shouldn’t exceed 110% of its rating.

Preparing a Report

Once you finish, it’s time to write a report on the harmonic study.

Here is what you should add to it:

  • Any general system info you have? That means lists of machines, branches, buses, etc.
  • The bus input data should have everything from ID and name to nominal voltage and harmonic limits.
  • The configuration of the system with engineering data revision. Add info about the input data, simulation, and solution.
  • A full report on the basic lead flow.
  • The spectrum of harmonic sources, including place, phase angle, and magnitude.
  • If you have overloading of the filters, cables, and transformers, add that info to the report.
  • Add that info to the report if you have overloading of the filters, cables, and transformers.
  • Reports on harmonic voltages for branches and buses. Make sure to add reports for each frequency.

Conclusion

Harmonic has effects on multiple parts of the system.

Therefore, it can cause many issues in the setup.

That’s why harmonic analyses and studies can help to deal with these problems.

Remember that cables and wiring are an important part of any setup.

If you need top-quality solutions, don’t hesitate to contact Cloom today!

Automatic Transfer Switch Testing Procedures: When and How to Do Them?

automatic transfer switch

What happens when the primary power source goes off?

An alternate source starts operating and powers the electrical equipment. 

How does this happen?

A transfer switch switches the electrical loads between two power sources. 

Sometimes, these transfer switches are manual.

An operator throws the switch whenever the two power sources lose or gain power.

However, now you can find an automatic transfer switch.

This switch has a specific control panel system that makes the switch automatic.

The control panel detects the primary source failure and leads to the start of the engine generator.

To ensure that the ATS works properly, you must conduct ATS testing.

Here are the helpful automatic transfer switch testing procedures.

How do Automatic Transfer Switches Work?

The automatic transfer switch is a self-acting device.

The control logic of the switch is automatic and microprocessor-based.

It regularly monitors the frequency and voltage of power sources.

In general, automatic transfer switches connect to the primary power source or utility by default.

However, when the primary power source fails, it connects to the alternate power source, i.e., a generator or backup utility. 

The switch transfers the load to the primary power supply on normal power restoration. 

You have to install these switches at the location of the backup generator.

NFPA guidelines for automatic transfer switch testing:

  • You must do inspection and operational testing.
  • Test all the EPSSs and internal and mechanical components once a month.
  • Operate the automatic transfer switch monthly.
  • You must perform an electrical function test periodically, including transferring the switch to the alternate power source from the standard source and returning it.
ATS installed under a building water

Image: ATS installed under a building water

Automatic Transfer Switch Testing Procedures– Monthly Automatic Transfer Switch Functional Testing

Most facilities, such as hospitals, data centers, factories, etc., require continuous power to deal with power failure circumstances.

They use an emergency system for alternate power sources.

This can be an engine generator or any other backup utility. 

If your automatic transfer switches (ATS) do not work, it may lead to serious issues.

Thus, you must do operational testing of automatic transfer once a month to ensure the smooth working of the switches. 

Precautions to take:

  • Firstly, make sure that you close the enclosure door of the generator set to prevent injury.
  • Secondly, ensure that the normal and emergency power sources should be there.
  • Finally, ensure that the emergency power sources should be in working condition.

Follow these steps for electrical operation transfer testing of an ATS and standby generator

  • First of all, turn the isolation handle anti-clockwise to the test position. This will turn on the transfer switch connected to normal and normal source-accepted lights.
  • Now, turn and hold the transfer control switch clockwise to the transfer test. The delay to the engine start timer begins its cycle. This cycle will take 15 seconds until the engine starts and runs. When the cycle completes itself, the “engine start contacts” close, and it starts the generator. With this, the emergency power source lights will turn on.
  • This triggers a 2B time delay, and after this, the transfer switch will work in an emergency position. As a result, the transfer switch connected to the emergency light or the S2 position LED turns on. Along with this, the transfer switch connected to normal will turn off.
  • After the feature 3A time delay, the transfer switch will return to the normal position.
  • To retransfer immediately, turn the transfer control switch in an anti-clockwise direction to retransfer delay bypass. As a result, the transfer switch connected to normal will turn on, and the transfer switch connected to emergency or the S2 position LED will go off. Now, turn the isolation handle clockwise to the connected position.
  • After the feature 2E time delay, the generator will stop. The cycle of the delay engine stop timer starts. During this time, the generator set runs without load.
  • It is important to give a minimum 5-minute delay for the unloaded running of the generator. Let the engine cool down during this time. 

With these steps, you can verify whether:

  • All the functions are running correctly when the load shifts to an emergency power source in case of primary source failure.
  • S1 (source1) LED and S2 position LED are working properly.
  • There is any vibration or noise during operation.
  • All the time delays during the load transfer are working correctly. 

Automatic Transfer Switch Testing Procedures– Annual preventive transfer switch maintenance process

To ensure the reliability and life of the automatic transfer switches, proper maintenance is important. 

The switch uses dangerous voltage that can shock, burn, and even death.

Thus, make sure that you disconnect ATS with the normal power source and the emergency power supply system before any automatic transfer switch maintenance activity.

  • First, conduct a visual inspection and look for any dirt, dust, or moisture. Remove all the dust with the help of a soft brush or a vacuum cleaner. Clean the moisture with a cloth.
  • You will find a manual operator handle on the switch for maintenance purposes. You must check for any issues in manual operation. 
  • Next, remove the transfer switch barriers. Check all the internal components and contacts of the switches. Contacts must last till the life of the switch. Reinstall all the barriers carefully.
  • Due to harsh operating conditions, the lubrication on the switch may get lost. Thus, apply lubricants on all movements and linkages.
  • Then, check the connections of all cables and wires. Re-tighten them if required.
  • Finally, ensure the switch has manual transfer warnings to avoid accidents.

Automatic Transfer Switch Testing Procedures–Who performs this test?

If it is a normal automatic transfer switch testing, any local person can do it.

However, for advanced testing procedures, you have to contract out this task to experts.

When doing so, ensure the contracting company meets all the safety requirements of the OSHA (Occupational Safety and Health Administration).

Also, the company must have industry-trained technicians to do this job.

Having qualified personnel means they are very well familiar with the procedures, related risks, and safety procedures of the ATS.

Conclusion:

Testing an automatic transfer switch ensures that you get a continuous power supply.

It will also ensure that the load transfer process, from primary power supply to emergency power supply, is efficient, safe, and fast.

During the installation of ATS, if you need any help regarding wires and cable assemblies, contact Cloom.

We deal in high-quality ones for your electrical system needs.

How to Test an Electric Motor: A Complete Guide on it

How to Test an Electric Motor

Using motors is a part of your work if you belong to automotive, steel, or any other heavy machinery.

Indeed, these devices have made hectic tasks a matter of no time by converting electrical or hydro energy into mechanical power.

Useful as it sounds, it comprises complex parts for its function.

If anyone malfunctions, it can cost you a lot of time and money.

Hence, you must know how to test an electric motor with time.

What to Test on A Motor?

For electric motor testing, you must know what parts or factors to check periodically to minimize the potential delay.

Bearings and Shaft

The motor’s bearings are the component with most of the load on it.

As time passes, it is worn out and may cause damage to other machinery if not changed with time.

Therefore, you have to keep an eye on it.

Testing the bearing and the shaft is easy.

All you need to do is move it and check whether it is rotating smoothly.

If not, lubrication might help, or you must replace it completely with the new one.

Motor Windings 

In a motor, windings provide a path to current flow, creating a magnetic field that rotates the gears.

Besides, they play a significant role in motor function; you must inspect them regularly.

For that, you need a multimeter to see the ohm readings of the wires and terminals.

You will test the windings for each of the wires and check whether all the components of windings have a regular flow of current.

Then, you will test them with each other to check the shortage in phases.

Power 

As a motor runs on electricity, you must check its power supply.

For that, again, you can use a multimeter.

Excellent power ratings vary from motor to motor, so you must consider the type before choosing the threshold value.

Check the user manual before conducting a power test for complete guidance.

If done otherwise, you could complicate the process, wasting your time and damaging the motor.

So hire a professional if you don’t have any experience.

Motor Fan

While testing the components, people mostly forget it is the motor fan.

Not knowing how much it is crucial, you may not maintain it.

A fan can keep your motor cooler, increasing its life span.

Thus, you have to ensure it is clean and debris-free.

Meanwhile, you are cleaning your motor, make it a habit to rotate your fan and check whether it is moving smoothly or not.

If not, lubricate or change it to the new one to protect your motor from overheating.

Tools for Motor Testing

For conducting electric motor testing successfully, having a good tool kit on hand is crucial.

Digital multimeter (DMM) 

A multifunctional tool, a digital meter is a power pack of voltmeter, ammeter, and ohmmeter.

You can use a multimeter to check a circuit’s power loss, excessive current levels, and fluctuating resistance readings.

A screen to see the value on a DMM, a dial to choose the value to measure, and input jacks to connect the test leads. 

Clamp-on ammeter 

Used to measure both AC and DC currents, a clamp-on ammeter measures the strength of the magnetic field produced around the conductor.

A pair of jaws on this ammeter makes it easy to clamp it on the wire or other testing object.

Using a clamp meter, you can check the current without disconnecting the system.

Clamp-on ammeters are convenient and hence the first choice of technicians. 

Meg-ohmmeter

With a megger or megohmmeter, you can test the insulation level of a wire.

It does this by giving a high volt, low DC charge and assessing the current leakage, if any.

After that, it displays the value on the screen, making it handy for everyday insulation maintenance. 

Non-contact thermometer

Ideal for determining the temperature from a distance, a non-contact thermometer measures thermal radiations emitting from moving or hard-to-reach parts of the machine using temperature sensors.

Likewise, it is shaped like a radar gun, so you can use it to check the temperature of an apparatus from a safe point.

Power quality analyzer

Another multifunctional tool for testing motors, a power quality analyzer, is more expensive than the above.

But the functions it provides, such as

  • Calculating power in neutral as well as all three phases
  • Measuring Inrush currents and swells
  • Integrating with compatible software makes it worth every single penny 

Methods of Motor Testing

For a good maintenance program, you must plan out the technique you choose from several methods.

Typically, there are two classes of motor testing;

  • Online dynamic testing provides the data for power quality and specifies under which conditions you should operate a motor.
  • With this testing, you should collect the readings on power condition, voltage level, imbalance, load, and torque from a moving motor.
  • You can then analyze these values and assess the motor performance effectively.
  • Whereas offline static analysis determines the functioning of each part in an electrical motor and given current and voltage. You can use it to check for broken rotor bars, end rings, and misalignment in the components. To maintain your motor, you must perform it regularly when the machine is not running to figure out issues on the spot.

Some of the common issues motors face are the rotor and winding failure.

You can test the motor with various proven methods to lessen these problems.

Electric Motor Rotating Test

To avoid damage to the machinery, you have to check the direction the motor is rotating before connecting it to a load.

While checking a three-phase motor, you will need a phase rotation meter with six leads, three on the motor and three on the supply side.

Motor Impulse Test

The impulse test tells you how your system will withstand sudden voltage and power surges.

Usually, the motor gets overvoltage due to weather conditions, voltage variations from AC to DC, and voltage equipment changes.

Therefore, you have to test the motor after these situations occur.

Insulation Resistance Test

Resistance of insulation decreases with the increase in its temperature.

This test ensures the motor has adequate resistance so that the current flow does not stop.

According to IEEE 43 standard, this test needs a temperature rectification of 40C.

Wound Rotor Test

With a wound rotor test, you can reach the main cause of the problem as it isolates the statorrotor, and resistance bank.

Like the working of a transformer, any changes in the rotor (secondary) circuit having a resistance bank will cause a change in the stator (primary) circuit and vice versa.

Megger Testing

Megger tests check for the insulation resistance of a motor.

As a good approach, Combining it with another type of test is best to detect all the faults in winding completely.

Winding Resistance Testing

With a digital multimeter, you can check for winding resistance to ensure you have wired all the circuits properly and have no loose connections.

In addition, this resistance also allows enough flow of charges through the coil for its effective working.

HiPot Test

High Potential Test reviews the weakness in the insulation of cable or wire.

You will apply current between the circuit and the motor frame to conduct this test.

Notice the leakage current and the corresponding resistance of that point.

Note the values as lower readings of meg-ohm show damaged insulation.

Surge Test

Note that you have to perform a Surge test under IEEE 522 standard.

The surge test helps in the detection of potential motor burnout and failure.

It indicates the voltage level according to the type of motor and its winding.

You can identify failing insulation and dead shorts with this test.

Core Loss Test

Core Loss tests check the difference between the input and output power and check it against the standard value.

It indicates the motor requires replacement to maintain the system’s highest performance.

Polarization Index Testing

PI test checks for the fitness of the motor.

Correspondingly, it gives you the stats on how much moisture and dirt is built inside the motor and its effects on insulation.

For that, you take the values of insulation 10 minutes apart.

Their ratio is your Polarization index value.

DC step voltage testing

Step Voltage also looks for the insulation integrity in a circuit.

You should perform it after finding the value of PI and increasing the voltage after a given time.

Outcoming values will plot a graph for you, which is if non-linear, your motor has insulation problems.

You have to conduct this test under IEEE 95 Standard.

Voltage Drop Test

The voltage drop test provides information about the resistance in high ampere circuits.

Similarly, it is one of the quickest tests for evaluating a circuit operation’s quality.

You can take the voltage drop values as a sign of maintenance and cleaning the motor circuitry.

Vibration Analysis

Vibration analysis is an online test that gives the data on a motor according to a schedule.

Using a MEM sensor, you will collect the data in a waveform shape.

With this test, you can check for bearing defects, resonance conditions, rotor and stator faults, and broken welds or loose bolts.

Rotor Bar Test

To examine any damaged rotor bars, you can apply the growler, single-phase, and high-current rotor tests.

These tests allow you to look into the discontinued current flow and fluctuations.

In a high current rotor test, you can also perform a visual inspection on the surface of the rotor to reveal damaged spots using an infrared camera.

Automated Test

With the advancement of technology, modern motor testing uses the benefits of automatic fault testing methods.

Therefore you can easily find an automated diagnostic tool to perform all electrical tests in one device.

By using automated testing, the chances of having operators error minimize to 0, and you get more accurate results.

Test Single-phase Electric Motors

For testing a single-phase AC motor, follow these simple steps.

  • General Inspections; See the basic wiring of the motor. Rotate the shaft and fan with your hand to see if they are running smoothly or not. This way, you will inspect that the basic components are good for the run.
  • Capacitor test: Test the power supply and capacitor terminal voltage with a multimeter. The capacitor voltage should be 1.7 times more than the supply Voltage.
  • Extension Cable Test; For this test, power off the system first. Then test the points near the motor and power supply. If the circuit is intact, the tester will beep.
  • Winding Resistance Test; Test the resistance readings by removing all the extra components. Measure the resistance in each winding. If they conform to designated values, your motor is ready to roll.

In case your motor doesn’t pass the capacitor test, check/replace the capacitor or wiring.

Also, if it fails the extension test, check the cable or connector; if it fails the winding resistance test, replace the motor.

Testing Three-phase AC Motors

For testing a three-phase AC motor, follow these simple steps.

  • General Inspections; See the appearance of the motor and look for any burnt or damaged areas. Rotate the shaft and fan with your hand to see if they are running smoothly or not. After that, test it with an amps test and access the value compared to the values proved on the motor manual.
  • Earth Continuity and Resistance Test; With a multimeter, measure the resistance between the motor frame and the earth. It should be less than 0.5 OHMS, or else it requires repairing.
  • Supply Test; If you have a 230/400V three-phase motor, the normal voltage value will be 230V between phase to the neutral point and 400V between supply lines. Check it using a multimeter and ensure the good condition of the motor.
  • Winding Continuity Test; Test the continuity from phase to phase. If any phase fails the test, the motor is burnt; otherwise, the motor is good to go.
  • Winding Resistance Test; Test the resistance readings from phase to phase. Each winding will give you nearly equal value to each other. Otherwise, there is insulation breakage.
  • Insulation Resistance Test; Inspect the insulation readings from phase to phase and phase to the motor. Note that failed insulation resistance indicates a failed motor circuit and needs change.
  • Running Amps Test; Using a clamp-on meter, check the full load amps or FLA and compare it with the value on the nameplate or manual. If values deviate from each other, you need to change the motor under test.

Prepare your Test Program

You can prepare your testing program by taking help from the following steps.

  1. Start personal preparation by taking deeper knowledge of the system and circuits
  2. Analyze the machine you will test based on its operation ratings, safety, logic, and environmental criticality. Discuss these factors before the test with your team for deeper insight.
  3. Check your weapons. See the tool’s batteries, power cords, voltage clips, and updates on software if you are using one.
  4. Check the operational status of your tester before going into the field.
  5. Test as many circuits with maximum load as possible since you devote time and energy to it.
  6. Confirm identified anomalies, as it exists if you are getting a compromised reading during the test. If not, you can have a bad reputation in the market or be accused of using bad tools or both.
  7. Try using different technologies in the same test environment to minimize erroneous results.
  8. In the end, Generate readable reports so your clients can see the results and benefit from them.

Conclusion

Wrapping up the discussion, testing a motor at the right time can save you from damages in the future.

You can conduct different tests and check their windings, frames, and insulation for this purpose.

However, it is advised to conduct the test periodically to minimize the chances of a burnt electric motor.

Testing motors often require repeated wiring and is tough when the machine is complex.

Here at Cloom, we offer custom wiring assembly with attention to each detail so that your devices are easy to maintain. 

Short Circuit Analysis: Why and How to Do It

a burnt cable due to a short circuit

Have you seen a sudden blast or shock wave in a power system?

Well, most of the blasts occur due to an electrical fault.

Short circuit analysis is harmful to every power system.

It can damage electrical equipment. It can also injure or harm the working personnel.

Short circuit analysis is an important part of electrical maintenance.

So, you had better do it when you add new cables, circuit breakers, etc., to the power system.

However, before that, you must know what a short circuit is.

What is a Short Circuit?

When high currents exceed the limit of protective devices, it becomes dangerous.

It occurs when two points of different voltages connect.

And the electric current travels to an unintended path of low resistance.

Owing to the low resistance, there is a high flow of current.

Contact between two points of different voltages creates the wrong path.

So, energy is rapidly released in the form of heat and magnetic fields.

This creates a shock wave, overheating, explosions, fires, or circuit damage.

Most of the time, short circuits occur due to faults.

However, at times, you can do it for testing purposes.

short circuit and burnt cable

Image: short circuit and burnt cable

In an Alternating current system, a short circuit can occur:

  • If one phase touches another phase
  • T phase touches the ground
  • If the phase touches neutral
  • If the windings of a machine touch each other in one phase

Direct current system results in a short circuit in the following circumstances:

  • When two poles touch the ground
  • When there is contact between poles.

Different Faults that Occur Due to Short Circuits

Short Circuits can lead to faults within the system. They are:

Bolted fault: Sometimes, you bolt two conductors of different voltages together or to a power source.

This source of power is bolted to the ground.

This results in a bolted fault.

No fault resistance exists, so the highest possible current passes through the system.

Bolted faults are quite unusual and occur by chance only.

You can use bolted faults to speed up the operation of protective devices.

Arc fault: This fault occurs when current flows through two conductors which are not in contact.

When there is high system voltage, an arc forms between system conductors and the ground, this arc has very high resistance.

A simple overcurrent protection device cannot detect this arc. It can cause severe damage to the cables before becoming a complete short circuit.

Also, it may lead to arc blast or arc flash, leading to severe injuries.

Image: electric cord exploding

Ground fault: A wrong connection between the conductors and the earth results in this fault condition.

The current flows through a low-resistance path to the ground.

This results in dangerous circulating currents that damage the equipment at high voltage.

This path may lead to serious injuries when it passes through the human body.

Most of the power systems are designed to bear one ground fault.

However, a second fault leads to electrical components failure.

The electrical shock from the ground fault also stops the human heart from functioning.

Symmetrical faults and non-symmetrical faults:

Polyphase systems can have either symmetrical or non-symmetrical faults.

The differences between them are:

  • Symmetrical fault current affects all phases equally. On the other hand, non-symmetrical will affect only a few or all phases unequally.
  • You can analyze symmetrical faults. However, the non-symmetrical fault current is difficult to detect.
  • Non-symmetrical faults are common, while symmetrical faults account for only 5%.

Why do Short Circuits Damage Equipment?

Sudden short circuit results in extensive equipment damage.

Two phenomena increase the risk of equipment damage during a short circuit event.

Image: overloaded circuit board

Thermal phenomenon: Short can lead to energy releases through intense heat.

This is the thermal phenomenon. This heat damages an electrical circuit in various ways:

  • The melts the ends of the conductors.
  • Causes damage to the insulation.
  • It generates electric arcs.
  • It destroys the thermal elements in the bimetal relay

Electro-dynamic phenomenon: Sometimes, the short circuit current creates high mechanical stress.

This results in physical damage to the conductor’s windings and conductors.

Also, it can result in the repulsion of contacts within conductors.

Protective Devices for Short Circuits

An overcurrent situation is dangerous for equipment and humans.

In such situations, you need to use a protective device.

The protective device detects any fault current. On detection, it trips the circuit at once.

This prevents the current from reaching its maximum limit.

These electrical protection devices have two features:

  • Breaking capacity: When a high current travels, the protective device will break the circuit. The highest value of this current is the breaking capacity.
  • Closing capacity: The maximum short circuit current at which the device will reach its rated voltage.

An electrical circuit has different power system protective devices. However, the most common type is:

Fuse: This protective device gives you high breaking capacity.

Circuit breakage occurs even at low voltage. However, you have to replace it once it trips.

The fuse protects the electrical circuit from electro-dynamic stress.

This protective device is suitable for phase-by-phase protection.

electrical fuses

Image: electrical fuses

Circuit breakers: Circuit breakers break the circuit automatically in a short cut-off time.

Circuit breakers separate the load from the power supply.

This will protect the electric circuit from damage.

Unlike a fuse, it protects the electric circuit against thermal and electro-dynamic effects.

electricity distribution box with circuit breakers and wires

Image: electricity distribution box with circuit breakers and wires

Ground Fault Interrupter: The current flows in the charged conductor in an electric circuit and returns through the neutral conductor.

Ground Fault Interrupter (GFI) detects any difference in this circuit current.

If there is a difference in circuit current, current flows stop at once.

This protective device can protect you from the shock wave.

You can use ground fault interrupters in your homes for bathrooms and kitchens.

This comes inbuilt in an electrical socket. You do not get over-current protection through a GFI.

As a result, any circuit that uses a GFI also uses fuses or circuit breakers.

Along with these protective devices, there are several other protective devices.

You can use them to 

  • Find any changes in the voltage level and current
  • Observe the ratio of voltage and current
  • Offer protection against over-voltage and under-voltage
  • Detect phase reversal and reverse current flow

What is a Short Circuit Analysis?

You can do this analysis for short circuit fault current calculations.

During an electrical fault, a certain current flows through the electrical system.

You can calculate the maximum fault current with this circuit study. However, don’t miss the contribution from generators and synchronous motors when calculating maximum fault current.

Also, take note of induction motor contributions. 

Compare these values with the equipment ratings of short circuit protection devices and installed electrical equipment.

Ensure that electrical equipment can bear the short circuit energy at each point.

Create fault currents at different locations for complete information.

Now, repeat the study. With this, design a suitable relaying system to protect the devices.

Your equipment will fail to handle a fault current in low-rating power systems.

This leads to major destruction in the power distribution system. 

For circuit study, you need power system analysis software that complies with IEEE standards.

For large systems, do circuit calculations for switchgear and relay settings. 

Short circuit analysis is important to meet several standards. 

According to NEC110, you must do short-circuit study for all electrical equipment and power systems.

This is important for NEC and NFPA labels.

For this, you need to meet the guidelines of two common standards; One is ANSI, and the other is IEC.

With ANSI standard guidelines, you can select power circuit breakers.

However, you do not get any information related to NEC110 labeling. On the other hand, the IEC 60909-3:2009 standard is more general.

Its guidelines help in performing a study of an asymmetrical circuit in a 3-phase electrical system.

You can use either of the calculation methods. You will get almost similar results.

Benefits of Short Circuit Analysis

Conducting a short circuit analysis is beneficial for your installation. 

  • Firstly, it avoids unplanned outages and any disturbances in essential services.
  • Secondly, it reduces the risk of fires and equipment damage.
  • Thirdly, it ensures the safety of people.
  • Finally, it ensures the safety and protection of the power system. This makes the system more reliable.

Software for Short Circuit Study

Some of the software programs for this are:

  • ETAP
  • SKM power tools
  • Easy Power
  • PSS

How to Conduct a Short Circuit Calculation

To apply the coordination of protective relays, a short analysis is essential.

Follow these steps for the circuit study.

Firstly, collect information related to all electrical components.

Secondly, draw a linear network of the system. The diagram must show the connections of all electrical components. You can also find cable impedance with this power system diagram.

Thirdly, select the suitable short circuit study software. Put system data as input. Do short-circuit calculations at different points. Put these results as output.

Now, organize the results. Compare the short circuit current calculations with the short circuit rating. The circuit values you compare must be from the same point. If the short circuit current is higher, mark that as dangerous.

Finally, prepare a detailed report of the study.

At last, suggest any corrections that need to be made.

Conclusion:

Don’t hesitate to do a circuit study if you doubt a short in an electric circuit.

Short circuits result in damage to wires and cables.

So, if you want high-quality cables and wires, Cloom is here to help you.

We help you with top-rated wiring harnesses and cable assemblies.

Contact us for more details.

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