Ground Fault Circuit Interrupters and a Generator Question

[MikeT]

Hi All,

I am in the process of running an underground 30 Amp line to my trailer so I can avoid having my power cord run across my driveway. In Canada, we are required to have a GFCI circuit for outdoor 15 amp circuits so it would seem  logical that the same would apply to a 30 amp circuit.  However, when I was researching this on the web, most of the comments said it was not necessary.  I also went to our local library and looked at the electrical code with no luck.  I'm sure the answer was somewhere in the 1000 page document, I just did not have time to find it!
If anyone can shed some light on this it would be appreciated.

On another note, is it necessary to ground a generator?

Cheers

Mike

[Merlin]

In the U.S. the National Electric Code requires an outdoor 30 or 50 amp power outlet to have a GFCI. (15 and 20 amp too). It's a minimal cost for important outdoor electrical safety. (Per the NEC)

Generators connected to a building are grounded via the building ground. Generators powering equipment from the generator outlets are grounded via the generator frame and there is no need for a separate ground. (Per OSHA).

Put your underground wire in per code. Where I live local code is 19". Use direct burial wire and/or conduit.

[MikeT]

Thanks Merlin,

1.  I'll check further into the GFCI rules in Canada.  Prices for a 30 amp GFCI range around $600.00 but I'm still looking.  One of the problems I have is that Federal Pioneer StabLok breakers are becoming obsolete.

2.  In Canada, trench depth is 24 inches from Grade level down to the top of the cable/conduit and then another 3 inches of sand under the cable, so 27 inches.

But, if you are adding mechanical protection by way of concrete or treated lumber (untreated cedar may be okay depending on the province) you can reduce the grade level to cable/conduit to 18 inches + the sand under the cable, so 21 inches.

Both call for 3 inches of sand above the cable but I'm going 6 (I have a lot of sand!).

3.  I saw a ground terminal on my inverter and made me wonder if I needed to ground it when plugging in to the trailer.

[Merlin]

Check again on that breaker cost. 2 pole 30A GFCI breakers for 240V power can be expensive, but for your camper you just need a single pole 120V GFCI breaker and here in the U.S. those are only $56US at the Home Depot.

Inverters are different than gas generators. Some have the neutral bonded to the equipment ground, some don't, and some are actually both. They bond the neutral to the ground when you use their receptacles but do not bond those when used hardwired to an electrical panel. It's important to have only one place in the electrical system where the neutral and ground are connected. The operating manual for the inverter should tell you what to do about the ground, so I won't guess.

That's a deep trench!  I suppose the sand is to keep the wire from chafing on stones.

[MikeT]

I found the breaker you identified at Home Depot.  Unfortunately it is not an FPE StabLok.  I will keep looking.  Interestingly, I noticed that you can buy a 30 amp RV Pedestal that comes with a 30 Amp plug and a 20 Amp duplex plug.  The 30 Amp is not GFCI but the 20 Amp is.  That's not to say that the breaker in the house panel isn't GFCI.  Some of the articles I have read is that 30 AMP GFCI is not necessary but may be coming soon. One of the obstacles is the thousands of campsites that would have to modify their systems to accommodate this change.  My investigation continues!!

Thanks for the info in the Inverters.