Portable generator without grounding electrode

[Mustwin351]

I just started work at a college that occasionally has events on campus that require portable generators. The generator supplies a panel that feeds cord and plug connected equipment. The city makes us drive a ground rod as we should. My question is if I have the generator on a cart to move it around and I attach/mount the panel and receptacles to the generator then can I get away without having to drive a ground rod? Granted the AHJ would make the call but I am wondering as far as the NEC is concerned if that works.

250.34 is the article.

 

[jumper]

I say no GES needed.

 

[zbang]

250.34 says that both portable and vehicle-mounted generators don't need a GES under most circumstances. IME AHJ's also disregard that quite often. (Heck, some AHJ's don't realize that the GES is not part of the fault current path, either.)

However... if the panel you mentioned is "hard-wired" to the generator but separate from it and not cord/plug connected, then the whole thing needs a GES.

The question really gets into the specifics of the setup. How big a generator are we talking about?

 

[petersonra]

250.34 says that both portable and vehicle-mounted generators don't need a GES under most circumstances. IME AHJ's also disregard that quite often. (Heck, some AHJ's don't realize that the GES is not part of the fault current path, either.)

However... if the panel you mentioned is "hard-wired" to the generator but separate from it and not cord/plug connected, then the whole thing needs a GES.

The question really gets into the specifics of the setup. How big a generator are we talking about?

Just curious where it says that in the code.

 

[petersonra]

I just started work at a college that occasionally has events on campus that require portable generators. The generator supplies a panel that feeds cord and plug connected equipment. The city makes us drive a ground rod as we should. My question is if I have the generator on a cart to move it around and I attach/mount the panel and receptacles to the generator then can I get away without having to drive a ground rod? Granted the AHJ would make the call but I am wondering as far as the NEC is concerned if that works.

250.34 is the article.

I don't believe you need a GES at all for a portable generator.

You might want to carefully read article 445.

 

[zbang]

(I can't figure out how to nest the quoting)
if the panel you mentioned is "hard-wired" to the generator but separate from it and not cord/plug connected, then the whole thing needs a GES.

Just curious where it says that in the code.

I'm reading that out of the exceptions in 250.34(B)(2)--

The generator supplies only equipment located on the vehicle or cord-and-plug-connected equipment through receptacles mounted on the vehicle, or both equipment located on the vehicle and cord-and-plug-connected equipment through receptacles mounted on the vehicle or on the generator, and

Applying Boolean logic to it, if the panel/equipment isn't mounted on the vehicle/generator and isn't C&P connected, then a GES is needed. A hard-wired feeder from vehicle to off-vehicle panel wouldn't be C&P connected. (There's probably a gray area for Camlok pigtails on a set of lugs, but I'll call that "mounted on" for discussion.)

That's my interpretation, but it's not one I'm going to push hard with the AHJ (unless it's on a concrete parking lot or the like). It's often easier to put in a rod than argue about it; usually faster, too.

 

[petersonra]

(I can't figure out how to nest the quoting)
if the panel you mentioned is "hard-wired" to the generator but separate from it and not cord/plug connected, then the whole thing needs a GES.



I'm reading that out of the exceptions in 250.34(B)(2)--


Applying Boolean logic to it, if the panel/equipment isn't mounted on the vehicle/generator and isn't C&P connected, then a GES is needed. A hard-wired feeder from vehicle to off-vehicle panel wouldn't be C&P connected. (There's probably a gray area for Camlok pigtails on a set of lugs, but I'll call that "mounted on" for discussion.)

That's my interpretation, but it's not one I'm going to push hard with the AHJ (unless it's on a concrete parking lot or the like). It's often easier to put in a rod than argue about it; usually faster, too.

Note what OP originally asked.

My question is if I have the generator on a cart to move it around and I attach/mount the panel and receptacles to the generator

 

[zbang]

Note what OP originally asked.

I did . That was the second part of the post. And if the generator can go on a cart, it's probably pretty small* and only has built-in receptacles. Which wouldn't ever need a GES.

*less than, say, 6-7kva

 

[Mustwin351]

I did . That was the second part of the post. And if the generator can go on a cart, it's probably pretty small* and only has built-in receptacles. Which wouldn't ever need a GES.

*less than, say, 6-7kva

Thanks guys. Just to clarify I’m not familiar with the acronym “GES”. Is that short for grounding electrodes?

 

[ActionDave]

Thanks guys. Just to clarify I’m not familiar with the acronym “GES”. Is that short for grounding electrodes?

pretty much. it stands for grounding electrode system. so grounding electrodes and grounding electrode conductors are included.

 

[Mustwin351]

pretty much. it stands for grounding electrode system. so grounding electrodes and grounding electrode conductors are included.

Of course. Thank you.