Hooking up 220 compressor

[mm08822]

Quite a few conflicting opinions. Decided to do some research for my own install.

NEC Article 430, deals with motors.

430.6(A)(1)
Exception 3 - (paraphrased) If the motor is marked with both HP and FLC
(aka FLA), use the FLC to determine the ampacity of the conductors.

430.22 Single Motor. Conductors that supply a single motor
used in a continuous duty application shall have an ampacity of
not less than 125 percent of the motor full-load current rating,
as determined by 430.6(A)(1), or not less than specified in
430.22(A) through (G)

In the OPs case, FLC = 22A * 1.25 = 27.5A conductors.

Misc:
Compressors are not covered by the NEC Appliances article.
Compressors are considered continuous duty motors.
The nameplate contains a lot of info that could be used in sizing, SF, Time, Temp, Code.

The exception you paraphrased is for appliances. An air compressor is not an appliance.

 

[Dneel81]

And this is why I'll pay an electrician (licensed) to wire up mine

 

[yatg]

Got it. Thanks.
"Exception No. 3: For a listed motor-operated appliance that is marked
with both motor horsepower and full-load current, ..."

5HP = 28FLC per table 430.248 multiplied by 125% per 430.22 = 35A minimum conductor
as was previously stated several times
This should be in Electrical FAQ post, not that anybody would read it.

 

[alfredeneuman]

waiting for for voltage correction 3 ... 2 ... 1 ...

You're a funny guy.....to somebody I suppose
Far be it from me to disappoint you>>>>>240