It would help if you had wires and cables for all types of electrical systems as they make the system function. Also, they have a considerable role in maintaining safety in wiring. Thus, you must pick the correct type of wire for a particular application. Wire diameter or gauge is the most crucial among so many different features. How? Let’s learn how the gauge affects the different technical specifications of the wire and have the AWG Wire Size Chart in detail.
Table of Contents
What is the American wire Gauge?
In North America, AWG is the standardized wire gauge system denoting the wire sizes. In this system, as the AWG number increases, the wire diameter and thickness become smaller. The smallest standard size in AWG is 40 AWG, and the largest is 0000. You can also call it the Brown & Sharpe wire gauge or just the wire gauge. They are for solid, round, conductive, and single-stranded electrical wires.
The AWG system came into existence in the year 1857. Before this standard, manufacturers used different methods to measure very confusing wire. The AWG system is similar to the Standard Wire Gauge system used in Britain. Several other countries use international metric standards where wire cross-section is represented in square millimeters, as mentioned in International Electrotechnical Commission 60228. The AWG system does not include the insulation size in the diameter dimensions.
Caption: cross-sectional wire area
Importance of American Wire Gauge
As the wire’s cross-section area increases, the wire’s resistance decreases. At the same time, the amount of current that a wire can carry safely also increases with the increase in the cross-sectional area. Also, a small gauge or larger diameter wire can have more power than the wire with a larger gauge.
AWG holds importance for wires which carry electrical current like home or business wiring, high power wires in automobiles, extension cords, etc. Using too small a wire, i.e., a very high AWG, can melt, overheat, and catch fire. Thus, to ensure safe electrical wiring, you must consider the wire’s current carrying capacity.
As larger wires use more metal, they are more expensive than smaller wires.
For wires that carry signals, such as video interconnect or audio hookup wires, the AWG is not as essential as it is for power wires. It is because the electrical signals in these wires have low power, and thus you do not need smaller AWG wires. Cable pair twisting and efficient shielding are more critical in these wires to maintain the integrity of the signals.
Caption: Gauge Wire
Relationship between the AWG thickness and other technical specs
The gauge affects the wire’s different technical specifications, which is why we say it has a considerable role in maintaining safety in wiring.
AWG to diameter
In this system, 0000 AWG indicates a wire diameter of 0.46 inches, and 36 AWG indicates a wire size of 0.005 inches. There are 39-gauge sizes between these two sizes which you can get through logarithmic calculations. The ratio of different sizes is 1 to 92 in diameter. So, you can say that each AWG step is around the 39th root of 92, which is approx. 1.12293 times changes in diameter.
You can calculate the wire diameter with this formula:
For gauge numbers 00,000, and 0000, you can use -1, -2, and -3 as gauges as they make more sense mathematically.
In the AWG system, the wire diameter doubles with every 6 gauge reduction, and the cross-section area doubles with every three gauge reduction.
AWG to Cross-sectional area
Commonly, when you refer to the size of a conductor, you talk about its cross-sectional area, which is expressed in mm2. To calculate the cross-section of solid round wires, you can use this formula:
Area = πr2, where r is the radius (1/2 of the diameter)
The gauge is ten times higher than the diameter in millimeters in the metric gauge scale, meaning a 50-gauge metric wire is 5mm in diameter. You must know that in the AWG system, the diameter increases with the decrease in gauge, but this does not apply to the metric gauge scale. Metric size wires are mentioned in millimeters instead of metric gauges to avoid confusion.
AWG to load current carrying capacity
The ampacity of the wire refers to its maximum current carrying capability of the wire. The table below mentions the copper wire current capacity. However, these are just rules of thumb. In reality, insulation, voltage drop, temperature limit, thermal conductivity, thickness, and air convection should also be considered.
Based on the AWG system, a smaller gauge or larger diameter wire conducts more electricity than a wire with a larger gauge or smaller diameter. As you decrease the AWG size of the wire by six, its cross-sectional area and the electric current amount increase doubles when AWG reduces by three. When you change the AWG size by ten, the cross-sectional area also changes tenfold.
As aluminum is not as good as copper in its conductivity, we consider aluminum as two gauges larger than copper when we compare the conductivity of both.
AWG to Maximum frequency for 100% skin depth chart
You can use this data for high-frequency AC applications. When alternating current flows through the wire, the current tends to flow along the sides of the wire. As a result, the effective resistance increases. The table below mentions the frequency at which skin depth equals the wire radius, which means above this frequency, you have to consider the skin effect while calculating the resistance of the wire.
Breaking force for copper wire
The table also shows the breaking force for copper wire. Here the estimation is based on the nickel-free soft annealed copper wire with a tensile strength of 37000 pounds/sq inch.
Caption: AWG Wire Size Chart
What is the American wire Gauge for Multiple Conductors Stranded Wires?
The AWG system primarily describes the size of single-stranded solid wires. However, when there are multiple conductors stranded wires, you can use AWG to get the cross-section of all the strands and then add them together.
In stranded wires, you usually use three numbers to define their measurements, representing the AWG size of the wire, the strand number, and the American Wire Gauge size of each strand.
For example, 23 AWG 5/30 means a stranded wire of 5 strands of 30 AWG or 0.0509 mm2 which is equal to the 23 AWG or 0.258mm2.
twisting two electrical wires
Applications for Different AWG Diameters
Wires have different physical and electrical properties, making them suitable for various applications. The wires with thin gauges are ideal for lightweight applications, and the thicker wires are suitable for heavy-duty applications.
Here are some uses of wires with different gauges.
- Gauge 4 wire: suitable for large heaters and furnaces.
- Gauge 6 wire: ideal for heaters, large air conditioning units, and the clothes dryers
- Gauge 12: small air conditioning units and outlets in residential areas
- Gauge 14 wire: suitable for electrical circuits, devices, and lighting fixtures
- Gauge 16 wire: ideal for light-duty extension cords
- Gauge 18 wire: suitable for low-voltage lighting and cords
Hopefully, with this information, you will choose the correct wire size for your applications. If you need more help regarding high-quality cable assemblies and harnesses, contact Cloom. We are a leading manufacturer of superior quality.