GFPE for Floor Heat Tape - Freezers
Hello all,
It's been a long time since my last post, so let me first say I hope everyone is doing great!!!
I am 100% "In The Office" now, and only see Job sites when doing a job walk, performing Project Management tasks (I know, i am a P.M.... don't make too much fun of me...), client meetings (AKA "Yawning Festivals"... hee hee hee), and the occasional Inspection.
It's taking some getting used to, but my field days are long gone!
Anyway, to the questions at hand:
I have a question regarding the installation of Heat Tape in Concrete Floors of Freezers + Coolers, which will maintain an ambient temperature between 0° C and -30° C; and the need for GFPE devices.
additional locations with the Self regulated Heat Tape will be Man Doors, Lift Doors and Condensation Drain Lines.
Referencing NEC (2002 version) Articles:
* 426: Fixed Outdoor electric De-icing and Snow Melting Equipment,* 427: Fixed electric Heating Equipment for Pipelines and Vessels.Basics:
The Floor Heat tape is inserted into PVC conduit, which is installed under the Concrete slab (set prior to pour). The purpose for this Heat Tape is to reduce the issues of Permafrost buildup under the slab, and maintain constant temperature within the slab, so as to reduce chances for cracking the slab.
It is something that needs to be active continuously.
Heat Tape for Doors ("Door Heat"), is to reduce issues with expansion / contraction of doors, which makes them un-openable.
Condensate Drain line Heat Tape - as the name suggests, keeps the condensed water in the Condensate Drain line from freezing up.
Now to the quoted articles:
Some Inspectors are quoting Article 426 with corrections to install
"GFCI's", not GFPE.
Others are quoting either / both Article 426 and 427, again referencing the use of
"GFCI's", not GFPE.
I mentioned the differences in Ground Fault Protection (plus the fact that the articles do not apply, except for the Drain Heat), only to get shot down with "Protection for Personnel" (not mentioned in the articles).
Problem with using any leakage detection with a trip threshold of upto 6ma, is some of the Heat Tape strips are long, and will eventually drain >6ma into the bonded sheath cover, thereby tripping a 6ma leakage sensing device (GFCI).
GFPE devices with leakage thresholds >/= 30ma, do not trip under normal conditions.
Only problem is sometimes it's difficult to get GFPE breakers for certain Panelboards.
My queries are:
1: Do these situations require GFPE?
2: Do they require GFCI (protection for personnel)?
3: Is there any type of "Stand-Alone" GFPE, for those situations where there are no GFPE breakers made, or readily available?
Looking forward to your comments!
Scott
