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Posted By: akmaster Portable Generator Grounding - 05/14/13 11:46 PM
Any portable generator that is hard wired to equipment or devices must be grounded to earth as I understand OSHA. If there are cord and plug connections then no ground rod is required. Is this correct?

Thanks

Greg
Posted By: HotLine1 Re: Portable Generator Grounding - 05/15/13 01:12 AM
A 'cord & plug' connection is the 'EGC' (equipment grounding conductor) It is not a GEC, nor a Bond.

The earth ground for a 'portable' (3-8+/-KW) is a much debated topic and common practice is to just run it.

Posted By: gfretwell Re: Portable Generator Grounding - 05/15/13 01:39 AM
I have always questioned why you would even want to ground a truly portable generator (cord loads only).
There is a modicum of safety in having the generator ungrounded. With no ground reference, there is no danger from a fault to ground.
Posted By: HotLine1 Re: Portable Generator Grounding - 05/15/13 02:22 AM
gfretwell:

I had this debate as an EC back in '05 regarding portable light towers. Diesel, 4-6 1000 watt MH floods, and 2-120 volt GFIs on board. (Towable units)

The AHJ wanted grd rods at each unit. I had 65 units spread out over grass, paved parking lots, quarry auxilary parking & a few municipal streets.

Discussions, and a polite request for an article number eliminated the rods.

Posted By: gfretwell Re: Portable Generator Grounding - 05/15/13 03:45 AM
There are a lot of small generators that do not bond the neutral, most notably the Honda inverters.
This really only becomes an issue if you try to hook one to a 3 wire transfer switch.

I lifted the bond on my 5.5KW genset because my plan is to connect it with my breaker interlock. I already have the pigtail mounted on the side of the house for it. So far we have not had an outage worth filling it with gas.
(2 years for me and 3 years for the guy I bought it from)
My UPS's carried me through the last one. It was funny sitting there with both PCs running and the TV, satellite etc still going. If the kitchen light had not gone off I might not have even noticed.

Posted By: akmaster Re: Portable Generator Grounding - 05/15/13 03:31 PM
OSHA says that any hard wired cord connected supply from the generator has to have a ground rod bonded to the frame of the generator. If you have cord and plug connected only, no ground rod is required.

Here is the article:

http://click.infospace.com/ClickHandler.ashx?du=www.osha.gov%2f...%2fgrounding_port_generator.pdf&ru=http%3a%2f%2fwww.osha.gov%2fOshDoc%2fdata_Hurricane_Facts%2fgrounding_port_generator.pdf&ld=20130515&ap=1&app=1&c=snapdov3a.5&s=snapdov3a&coi=771&cop=main-title&euip=70.195.4.96&npp=1&p=0&pp=0&pvaid=6d1c792782f74931a5905afa937d6da7&ep=1&mid=9&hash=A1E9D9E485178B3B64C4E759ABAE3F08

Thank you,

Greg
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