How can you tell what gauge your wire is?

Answer 1

Most good approved extension cords will have the data printed on the outside of the cable. It might look like 3/16, 3 conductor # 16 wire. The better cords and construction cords will be rated at 3/14 and 3/12 in that order.

Answer 2

Extension cords that are used by home owners are usually #16. They can go from 16 to 12 but as the wire size goes up so does the price of the cord. The length of the cords and the size of the connected load governs what wire size the cord should be.

On construction sites extension cords can range right up to #6 rated at 60 amps. These types of cords usually have a sub distribution panel connected to them and the panel is loaded with 15 amp breakers connected to receptacle outlets.

Answer 3

There should not be any amp numbers on an extension cord. The only numbers you should see is the insulation rating which might be 75 or 90 degrees C and the conductor count and wire size. It should look like 14/2, 14/3 or 12/2, 12/3. What ever the combination is, the first number is the wire size and the second number is number of conductors in the cord.

A # 14 conductor is rated at 15 amps, #12 at 20 amps, #10 at 30 amps. There are light weight extension cords that use #16 size conductors. My advice is to stay away from any cord smaller than #14. Best home owner cord is a #12 at 50 to 100 feet.

Larger that #12 is used on construction sites and are usually made to order, for different types of portable equipment, by an electrician using twist lock ends so that they don't accidentally get pulled out.

Answer 4

UK answer: Most extension cords are sold with 1.25 mm2 cable rated at 13 amp max, but some are sold with 1 mm2 cable rated at 10 amps max.

Answer 5

Meaure its diameter with a micrometer. Look that diameter up in a wire table.

Answer 6

The device that you use is called a wire mike. It is a type of micrometer. It looks like the picture above.