GFCI used as HVAC protection 1

[mickyeng]

Hi gents! Here comes a quick question.
Is it required to install a GFCI breaker as the protection for an HVAC Compressor? The size of the compressors 20hp, 25hp and 30hp 460 Volts. The FLA goes from 34.7 to 50.

 

[RRaghunath]

Separate earth fault protection is standard for motors larger than 30kW. For smaller motors, short circuit protection including that for earth faults is provided by Fuses/MCCBs.
Having said that, if the MCCB is being used and if the MCCB comes with optional earth fault protection element, it may help in providing more sensitive protection.

 

[LionelHutz]

There is no requirement for ground protection on those sizes of motors in the USA or Canadian electrical codes. Also, GFCI refers to the human protection circuit breakers and receptacles for 120VAC circuits so a GFCI is not something you'd use on that application.

 

[dpc]

Agree with LionelHutz. But also, check the installation instructions. Many of these package systems have UL approval based on the use of current-limiting fuses ahead of the equipment. So you may end up needing a fused disconnect at the equipment regardless of the upstream protection.

 

[davidbeach]

The code required "ground fault" protection simply means that what's there trips for a single phase fault. Could easily be the same breaker that trips for other faults.

I’ll see your silver lining and raise you two black clouds. - Protection Operations

 

[mickyeng]

So (davidbeach)in this case can we use a Motor Protection Circuit Breaker? MPCB