Wire size?

[nbhi]

Joe
Inspector to Inspector, If the nameplate states, 27.5 amp draw, then the conductor needs be be greater than 12 awg? Thats all I am asking.

[Greg Fretwell]

27.5 a is not that ambiguous, where it gets confusing is when the number is something like 23a that falls between the 240.4(D) and 310.16 rating (for #12). HVAC equipment makes this easier by actually giving you the max breaker size but in the case of a hardwired motor load you might have to do some pencil work to see if the breaker is appropriate. The general rule is the breaker can be 250% of the motor nameplate FLA and the wire size has to be 125% of FLA, using 310.16 rating and that might be at the 75c column if the motor has 75c lugs (and not wired with a cable wiring method like AC, NM or MC which limit you to 60c).

[Greg Fretwell]

It might be noted that as soon as you put a plug on a motor you lose these concessions because a user can come along and plug anything into that receptacle. That is the reason why we have 240.4(D) (the 15a-14ga, 20a-12ga rule) The installer has no control over what a user might plug in so they build the 80% safety factor into the allowable breaker size. 14, 12 and 10 gauge wire is the most likely to end up on a receptacle.

[George P. Wells, CMI]

Originally Posted by nbhi

What size would you say it is?

Conductors sizes are continously printed along the wire. When looking at a short peice, you may not be able to see the size markings but the visible portion of the wires in a panel are usually long enough to be able to see the markings.

[Mike Whitt]

Originally Posted by nbhi

Joe
Inspector to Inspector, If the nameplate states, 27.5 amp draw, then the conductor needs be be greater than 12 awg? Thats all I am asking.

Not an inspector but you are correct. For a Air Conditioner a #12 would be maxed out at 25 amps.

[Greg Fretwell]

The problem is when it is a cable. Individual conductors are usually not marked in cables, you need to see the cable jacket. That will usually be behind the drywall if this is a flush mounted panel.