Electric Heat Trace and GFCI

[frankft2000]

ARTICLE 427-22 says heat trace needs to have ground fault protection. The commercial heat trace job I'm bidding requires a contactor. The regular contactor is around $185, but the contactor with ground fault protection built in is $1200!!! My question is....Shouldn't a gfci breaker work properly and not nuisance trip, and still meet the requirements of 427-22?

 

[Cow]

You can use a GFCI breaker.

One industrial facility out here has a full 30 space QO panel board mounted in the back of a control cabinet completely filled with GFCI breakers for heat trace. That entire panel is switched on the line side with a 200 amp contactor that gets a signal from an outside thermostat.

 

[frankft2000]

Sounds like a good setup.

 

[don_resqcapt19]

While in many cases a standard 5mA trip GFCI will work, but with long runs of some heat trace, the normal leakage current will exceed that trip point. There are ground fault protection for equipment breakers with a trip point of 20 or 30mA that can be used for heat trace.

 

[iwire]

QO 30 ma GFP

http://www.schneider-electric.us/pr...ductDetail&partNumber=QO120EPD&countryCode=us

Don't let the $410 list price put you off, they list a regular QO GFCI breaker at $233.00