Wire Size Calculator

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About Wire Size Calculator

What is the wire size?

Knowing the correct amperage and wire gauge is essential whenever a circuit is expanded, rewired, or any new circuit is installed. The new wiring ought to be constructed using wire conductors that are appropriately sized for the circuit's amperage rating. To prevent excessive heat that could melt electrical wires and start fires, electrical wires must be larger the higher the circuit's amperage rating. The projected load on the circuit, the number of outlets or light fixtures, and the length of the circuit are some of the elements that affect the appropriate circuit size, as represented by amperage. However, it is crucial that the wire gauge utilised in the circuit is appropriate for the amperage of the circuit breaker once the correct amperage has been established.

The term "wire gauge" describes the wire's physical dimensions and its ability to transport current. It is assigned a fixed numerical identification that is inversely proportionate to the conductor diameter. Simply said, a smaller wire gauge number will result in a greater diameter. To make sure the cable transmits the necessary amount of current securely, it is essential to understand the sizes available. The resistance of the wire and its weight per unit length are also determined by the gauge rank. A common measurement and classification system for electrically conductive wire cable thickness called "American Wire Gauge" was created in the country. It is appropriate for defining gauges for non-ferrous, solid, round conducting wires. Knowing a wire's gauge enables industry professionals to quickly and readily decide whether it is suitable for a certain application because a wire's thickness impacts its electrical qualities (such as resistance and load-carrying capability). Additionally, information can be shared between parties, such as from a manufacturer to a consumer.

What is the purpose of wire size?

A wire has less resistance the larger its cross-section. Additionally, the more current (amperage) a wire can safely carry before overheating increases with its cross-section. Greater power can be carried by a wire with a bigger diameter and a smaller gauge. Generally speaking, a smaller AWG value is preferable over a greater AWG. For cables that will transmit electrical power, such as house or commercial wiring, extension cords, or high-power wire used in automotive or audio applications, AWG is crucial. High AWG wires that are utilised with too little wire risk melting, overheating, or catching fire. The current carrying capacity of a cable or circuit must therefore be taken into account. Larger wire requires more metal, which raises the cost. The AWG of the wire is less significant for signal-carrying lines like audio hookup or video interconnect than it is for power wire. There is no need for smaller AWG bigger wire because these electrical impulses are often low power. For signal integrity in these circumstances, adequate shielding and cable-pair twisting are more crucial than the strands' AWG.

What are the characteristics of a wire?

The wire's diamete. Given that AWG 4 wire is the largest wire available, it has the widest diameter. Given that it is the smallest wire, AWG 40 has the smallest diameter. Greater resistance is always present in smaller wires than in bigger ones. Because there is less space for current to travel through, this occurs. Simply put, current is the movement of electrons. A smaller wire provides less space for electrons to travel through it. Less space allows them to bounce off one another more easily. Friction, or resistance, is produced by this bouncing and rubbing. There is more area in wires that are larger. As a result, electrons streaming clash and bump into one other less frequently. As a result, there is less resistance or friction.

The cross-sectional area of a wire is its area. This was determined using the average area of a circle. The region is described using circular MIL (CM). A circle with a diameter of one mil has an area of one circular mil. A wire's CM area is equal to the mil diameter squared.

The number of feet a wire gauge will provide you with for every pound of weight is known as feet per pound. For instance, AWG 4 wire is the heaviest since it is the largest wire. Therefore, 7.918 feet of wire are sufficient to weigh one pound. The smallest wire, meanwhile, is AWG 40 wire. Therefore, 34,364 feet of wire are required to weigh 1 pound. If the required number of feet of wire is known, feet per pound is a reasonable way to estimate the weight of the wire that will be used.

The resistance of a wire is measured in ohms per 1000 feet. This can be used to figure out a wire's electrical resistance. The distance increases with the length of the wire. Therefore, as the distance between two points increases, more electrons are contacting both the wire's walls and one another. As a result, friction and heat are produced, producing resistance. Increasing resistance reduces current capacity. Less resistance is created when the wire is shorter in length. Greater resistance is produced when the wire is longer.

The amount of current that a wire can safely carry is known as its current capacity. Because they can hold more electrons due to their size, larger wires can conduct significantly more current than smaller wires. You can see from the table that an AWG 4 wire can safely carry 59.626 amps of current. Only 0.014mA of current can be carried safely on an AWG 40 wire. A wire may overload, melt, and catch fire if the amount of current it can carry exceeds its current limit. Therefore, exceeding this level is extremely risky and poses a fire safety issue.

What are the types and sizes of wire?

You can choose the gauge depending on the useful advice provided below.

  • Low-voltage lighting and lamp cords in 10 amps are run on 18-gauge cables.
  • Light-duty extension cords supporting 13 amps are made of 16-gauge.
  • Light fixtures, lamps, and lighting circuits of 15 amps are made of 14-gauge.
  • Kitchen, bathroom, outdoor receptacles, and 120-volt air conditioners supporting 20 amps all utilise 12-gauge wire.
  • Electric clothes dryers, 240-volt window air conditioners, and electric water heaters that support 30 amps all utilise 10-gauge wire.
  • Cooktops and ranges carrying 40–50 amps use 6-gauge.
  • Large electric heaters and electric furnaces are protected at 60 amps with 4-gauge wire.

Hopefully, this advice will help you make the right decision.