Art 426.28 requires GFPE protection for deicing and snow melting equipment. What would is the advantage to using GFPE vs GFCI? GFCI I believe trips at 5ma where GFPE trips at 30ma, so I would think GFCI protection would actually be safer. Would nuisance trips occur?
I'm not trying to circumvent the code but just curious why GFCI would not be allowed. I must admit, I have never even seen a GFPE breaker.
Leespark: Perhaps the following commentary from the '08 NEC Handbook.....
"Section 426.28 requires ground-fault protection of equipment for fixed outdoor electric deicing and snow-melting equipment. Rather than protecting the entire branch circuit, the ground-fault protection requirement is focused on protecting just the equipment itself. This affords the manufacturer and the user an option of providing both circuit and equipment protection or just the required equipment protection. This required protection for fixed outdoor deicing and snow-melting equipment may be accomplished by using circuit breakers equipped with ground-fault equipment protection (GFEP) or an integral device supplied as part of the deicing or snow-melting equipment that is sensitive to leakage currents in the magnitude of 6 mA to 50 mA. These protection devices, if applied properly, will substantially reduce the risk of a fire being started by low-level electrical arcing. It is important to understand that this required equipment protection is not the same as a GFCI used for personal protection that trips at 5 mA (± 1 mA)."
Reading that, IMHO it sounds like the GFPE is supplied as part of the de-icing equipment, to protect the equipment only, not the feeder.
I have not seen a GFPE breaker, and only circulating hot water de-icing systems.
I see the big advantage of "ground for protection for equipment" over "ground fault protection for people" as avoiding nuisance trips. This could happen due to a higher capacitance in the (possibly) long wiring of the element wiring of the deicing or snow melting equipment. Also, I don't see where 426.28 specifically precludes using GFPP (GFCI) to meet the requirement, as long as the device ALSO protects equipment. I don't see any requirement that the ground fault protective devices be specifically listed for this category of usage.
GFCI devices are not prevented from being used on de-icing equipment. But, many de-icing circuits inherently have leakage current greater than 5mA (the trip point of a GFCI),this usually happen with lengths exceeding 100'.
GFCI is a specific term for 'people protection'. GFPE is a generic term.
Square D calls their GFPE breakers Equipment Protective Device (EPD). The part number for a QO 30mA breaker is QOxxxEPD.