What Gauge Wire Should I Use

Whether you take a 30 amp or a twoscore amp breaker, wire size is of import. Here's how to make up one's mind what size wire you need for your billow.

Wire is sold based on several factors. The virtually of import role that will exist covered here is the gauge, sometimes referred to as AWG (American Wire Guess).

Gauge is a measurement of a wire, specifically its diameter. AWG is the standardized system of this measurement. Wire gauge is measured from loftier to low with higher numbers meaning a smaller wire size.

Precise wire sizing is essential for circuit breakers as it helps determine how much electrical electric current can catamenia through it and how much resistance it has. The nautical chart below will tell y'all approximately what wire size is needed for the amount of ability that will be running through the line.

Please note that the data within this article is intended simply equally general guidelines. For any questions, always consult a certified electrician, as well as your local electrical codes.

Wire Size Ampacity Nautical chart

In the nautical chart below, we outline what gauge wire you need for the maximum amperage, or strength, of the electrical electric current. Annotation that the judge tin sometimes vary between aluminum and copper wires. Below is the gauge size based on the more than usually used copper wires.

Maximum Amps	7	ten	15	20	30	40	55	70	95
Gauge (Wire Size)	eighteen	16	14	12	x	8	6	four	ii

Here are some more details nearly some of the more than pop amperage sizes. Remember that when you use an appliance, always check the amp requirements first. You can calculate this by dividing Watts by Volts.

10 AMP Wire Size

For a maximum of 10 amps, you'll demand a wire gauge of 16. Common appliances that require around 10 amps include: a toaster, a hair dryer, a vacuum cleaner, a radiator, a washing motorcar, a dishwasher, and a fridge.

30 AMP Wire Size

For a maximum of 30 amps, you'll need a wire judge of 10. The well-nigh mutual household item that requires a 30 amp circuit is a central air conditioner.Often, people living in RVs utilise 30, and sometimes l, amp systems to run all the appliances in the vehicle.

forty AMP Wire Size

For a maximum of xl amps, you lot'll need a wire gauge of 8. Many electric cooking appliances require 40 amps such as electrical cooktops.

fifty AMP Wire Size

For a maximum of l amps, you'll demand a wire gauge of 6. Fifty amp breakers are nigh often used to ability many different appliances. Nonetheless, a kitchen oven can alone require 50 amps. Many electric dryers also require a l amp breaker.

Reading Cable Labels

You lot'll often purchase wires in cablevision, but it'due south of import to know how to accurately read the product labels in club to buy the correct product. Hither's a quick await at what to remember:

First, you'll often see the AWG of the wire(south) in the cable. So for a xiv gauge wire, it will read "14."
Next, you may see an additional number. This could read in either of these 2 formats: "xiv-2" or "14/two." This number signifies the amount of service wires or conductors in the cablevision.
And so you may see a "G" or "w/G." Both mean that the cable comes with a footing wire, which does not count towards the total number of wires noted on the label already.

Circuit Breakers

When updating an appliance or air conditioner, it is important to determine the correct current draw.

If your excursion breaker is 20 amps, you cannot install a product that requires 30 amps. Information technology is not as simple as just irresolute the circuit breaker. The wiring to the appliance besides needs to exist changed.

Although, when the opposite occurs, the solution is easier. For instance, let's say yous were using an apparatus that requires 30 amps. If y'all supervene upon this with a new apparatus that only requires twenty amps, you lot will need to change the circuit breaker and outlet receptacle — but you do non need to change the wire.This is because a wire can safely conduct less ability than information technology was rated for without any potential issues. Nevertheless, a wire cannot comport more power than it was rated for, otherwise information technology could become hot and create a fire gamble.

Other Aspects to Consider

Wire length:

Under sure circumstances a large wire size may exist needed fifty-fifty if your amp requirement does not seem to justify it. Become to the next largest wire size if your run is more than than 100 feet, inside a conduit, or ganged with other wires where the heat dissipation may be inhibited. As with all electrical work, consult a professional person with any questions about special circumstances.

Wire material:

If yous are using a wire that is not made of copper, brass or silver, you volition want to check to come across if y'all need a different size. Aluminum wires are much less mutual than copper ones, and they as well vary from them in requirements : They offer 61% of the conductivity of copper wires but have simply 30% of the weight of copper.

What Will Happen With the Wrong Size Wire?

It is incredibly dangerous to use a wire that has a smaller gauge than needed. The wire could overheat and melt. This could lead to breaker or appliance damage and be a fire hazard.

Using a wire that has a larger gauge than needed is not unsafe. Information technology tin be an inconvenience, since a larger wire is usually heavier and stiffer, but it won't lead to any potential hazards.

Finding the right wire size is an essential step to any electrical project or circuit breaker ready-upward. It's especially important to remember that it'due south about more than simply the number — recall to consider all the possible factors when it comes to wire judge. The information in this commodity is but a guide — we highly recommend that you consult with your electrician, and cheque your local and national electric codes, earlier purchasing and installing wires.