Portable generator grounding

Not really inspection related.

I installed a transfer switch for a natural gas portable generator for my home. My whole goal for everything is that my wife can easily hook up everything if I am gone. The gas line is quick connect. The 30-amp cord is easy to connect and switch over from utility to generator. I have a ground wire already hooked up to the generator and the clamp just needs to be attached to the ground rod.

My question is, how safe would it be to use a welding ground clamp to attach to the ground rod instead of using a normal ground clamp?

What does the manufacturer specify?

Your generator must be properly connected to an appropriate
ground to help prevent electric shock.
Failure to properly ground the generator can result in electric
A ground terminal connected to the frame of the generator has
been provided (see Controls and Features for terminal location).
For remote grounding, connect a length of heavy gauge
(12 AWG minimum) copper wire between the generator ground
terminal and a copper rod driven into the ground. We strongly
recommend that you consult with a qualified electrician to ensure
compliance with local electrical codes.
Neutral Floating*
– Neutral circuit IS NOT electrically connected to the frame/
ground of the generator.
– The generator (stator winding) is isolated from the frame and
from the AC receptacle ground pin.
– Electrical devices that require a grounded receptacle pin
connection will not function if the receptacle ground pin is not
Neutral Bonded to Frame*
– Neutral circuit IS electrically connected to the frame/ground of
the generator.
– The generator system ground connects lower frame crossmember below the alternator. The system ground is connected
to the AC neutral wire


And what did he/she have to say?

Asked two different electricians. One said that it was a great idea. The other said I don’t know.

Is the generator set up as a separately derived system? If not the ground rod is not needed.


And exactly what question(s) did you ask? Their replies don’t fit the question that should have been asked, IMO.

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I would be concerned with loosing contact relying on spring force. You could install a normal ground clamp with 12 AWG wire pre-attached with some type of quick dis-connect / plug-in for the generator ground wire. You would have to protect the disconnect from the weather, of course… install within an electrical box, perhaps.


This is the generator. Amazon.com: Champion Power Equipment 100416 10,000/8,000-Watt TRI Fuel Portable Natural Gas Generator, NG/LPG Hose Kits and CO Shield : Everything Else

This is the transfer switch. Reliance 30-Amp Power Transfer Kit at Menards®

I assume you followed the Manufacturers installation instructions?

(No, I didn’t read through it).


same way as how I asked on here.

I did. Nothing about generator grounding in it.

Doesn’t sound like you’re using a transfer switch which also switches the neutral so the generator does not require it’s own grounding electrode system. This would be a non-SDS system where the existing GES for the building would still be used even when on generator power. Don’t forget your signs that are required by the NEC at the panel and the inlet.


Thanks, Robert. I appreciate it.

What about before it is connected to the building? a portable generator is to be started before load is connected.

The generator is connected to the inlet before starting and is started without connection to the load at the panel. Once connected to the inlet the EGC is connected directly to the building GES.

Also depending on the configuration the generator may need to have the neutral to ground bond removed within the generator.

702.11 Portable Generator Grounding.
(B) Nonseparately Derived System. Where a portable optional standby source is used as a nonseparately derived system, the equipment grounding conductor shall be bonded
to the system grounding electrode.

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Aside from grounding, some portable generators don’t work with all the things you need/want them to. I have a Honda 2000 that is great for camping but wouldn’t run my gas furnace when we lost power. There is something about the type of power it puts out and some appliances don’t like it. I’ll defer to people much smarter than me but I think it has something to do with the type of inverter in the generator. I know with RVs there a big difference between basic inverters and and “pure sin wave inverters”. When I researched why my gas furnace didn’t play well with my generator that is basically the information I got. This may be completely irrelevant to what you are trying to do but just wanted to share my experience in case it helps.

You’re correct some non-inverter generators are better at producing a near perfect sine wave than others. The more electronics involved the better the output needs to be from the generator. I’ve run my central AC from a non-inverter Generac without any issues.

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Electricians are mechanics, not electrical engineers.



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