I had someone contact me(subcontractor for Hughes communications) about installing a GFCI protected outlet on the roof of a C store for de icing eguipment used on a Satelite dish. They want a GFCI outlet in the store labeled "do not use, satellite eguipment only", then use the load side to go up and out to a single outlet on the roof. That part seems ok(although I had an outlet labeled"do not use" in another location that the oil companies insurance made me remove or allow use). It seems to me the exception to 210.8B allows for a dedicated circuit without a GFCI, which would limit nuasance trips. They say in their spec sheet that C Store employees should check to see if GFCI is tripped frequently , like thats going to happen. Of course I get this yesterday, its now -15 degrees with a windchill at minus 50. It seems real likely that I'm going to get on a roof and check this out
Ryan The outlet is for De icing the Sat. Dish. The dish has heat tape to keep snow off the face and the lnb has a wrap of heat tape also. The exception says for snow melting or deicing equipment?? Thats what it would be doing, it doesn't say roof snow melting??
You are right about no GFCI being required so long as you meet all the requirements of Article 426. But, there may be a reason why they wanted GFCI protection. Mike has the right idea, put the GFCI inside the break room, next to the coffee machine, or better yet make it feed the coffee machine AND the de-icer on the roof. It would be sure to be checked hourly.
It would seem to me that a dedicated 15 amp circuit with a GFCI breaker rated for 30ma trip setting (equipment use) would solve some of the issue. The tripping of a 5ma GFCI receptacle or breaker with a 5ma setting can be annoying but I say if it trips and can be reset, something caused the trip and the unit did what it was designed to do. Keeping in mind that a GFCI u-ground receptacle is designed for life/safety and must trip at no more that a 5ma current to ground. Given the odd ball types of devices that can be plugged into a U-ground, the reasons for a "trip" are endless but "nuisance" should be change to "misuse".
As a dedicated circuit one could use a NEMA configuration that rejects the use of 15R devices but allows the snow melting cable to be connected.
The breaker can/should be in a dead front panel with locking device unless the maintenance staff use the breakers as switches. This is a common capital cost reduction method for "quick and dirty" installations. The breaker is readily identifiable so mistakes are rare.
It would seem that the HUGHES people are requesting a GFCI type device. The customer is always right, right?
To eliminate the constant surveilance by staff, I like n1st's idea of a pilot light or some method of annunciation that's hard to ignore if the trip occurs.
-15 Deg F. with a 50 Deg F. windchill. That's almost a heat wave where I am today. -20 Deg Celsus with a wind chill of 38 Deg Celsius. (you do the math)
Any hoooo this is only the rant and raving of an old man.
Post a reply to the thread that lets us know what was done and its acceptability to the customer, insurance and inspection.