Does 250.32 apply?

[don_resqcapt19]

If I was engineering it I would probably want ground rods. You said some distance from the building. Makes this equipment more likely to sustain a lightning strike. Talking about pump equipment. Customer does have money to do it right. That's my view.

How does the addition of a grounding electrode at the equipment help protect from lightning damage? I could understand a lightning protection system providing some protection, but don't see a grounding electrode system doing much of anything in the event of nearby lightning.

 

[Finite10]

How does the addition of a grounding electrode at the equipment help protect from lightning damage? I could understand a lightning protection system providing some protection, but don't see a grounding electrode system doing much of anything in the event of nearby lightning.

Seattle, WA has a much smaller lighning strike hazard, compared to the south.
MAP

 

[charlie b]

Seattle, WA has a much smaller lightning strike hazard, compared to the south.

True, but not relevant to this installation. The site is a bit east of here, though it is also a low lightning strike hazard area. Even so, lightning is not a concern for the skids I mention in Post #1. They will be under the "canopy" that I talk about in an earlier thread, along with the manufactured housing units.

Thanks for the map. I was looking for something like that earlier today.

 

[Cow]

I'm glad we're allowed to get away with hitting "some" seperate structures with several branch circuits. I've never brought it up for discussion with the inspector though, because I don't want to know his official answer...:roll:

For instance:

The farms around here will often have a stanchion or standalone service with a house panel and control cabinet on it. That control cabinet will run the fans/augers/portable equipment on a series of grain bins. All the bins are near each other, but usually have a few feet between them making them all seperate. The farthest one could be 100-200 feet away from this service. We just run a couple conduits to each bin with the all the motor circuits in them.

Farms are usually the exception for me though, since I usually make it a point to treat everything like a seperate structure when I'm wiring it. By that I mean using a single feeder, main disconnect, grounding electrode, etc. But some things on farms just aren't practical to wire that way.

 

[220/221]

.



Well 'around there' you don't seem to follow a lot of the codes.:grin:

We just interpet things a little different than you do around there :grin: A little logic goes a long way.




Hypothetical question.

Landscape lights. Two circuits, seperate neutrals.

Does every JB/light require a ground rod?

They are separate structures.....right?

 

[charlie b]

I would not call a landscape light a "structure." I would call it "utilization equipment."

 

[Electron_Sam78]

We just interpet things a little different than you do around there :grin: A little logic goes a long way.




Hypothetical question.

Landscape lights. Two circuits, seperate neutrals.

Does every JB/light require a ground rod?

They are separate structures.....right?

I agree with charlie b. But for argument's sake let's say you put a post out and it had 2 separate receptacles and a light. If each of these needed a dedicated circuit then this structure would then have to have a small circuit breaker panel (assuming single phase is only available) and the circuit supplying the post would be a feeder supplying a CB panel and would be required to have a grounding electrode system installed.

Also just because something is manufactured doesn't mean it isn't built or constructed. They are synonymous. The point is that anything permanently installed that has a need for multiple circuits they want a ground rod installed.

 

[220/221]

I would not call a landscape light a "structure." I would call it "utilization equipment

utilization e?quip?mentEquipment that uses electric energy for mechanical, chemical, heating, lighting, or other useful purposes, such as an electric motor


I wouldn't call a post a structure but that's not my point. The UE is the light fixture. The JB is part of the structure that supports it.

Also just because something is manufactured doesn't mean it isn't built or constructed.

In my example, it was certainly built and constructed.

You used a box, wire, conduit and fittings to build/construct something.

The point is that anything permanently installed that has a need for multiple circuits they want a ground rod installed

Again, my example was permantly installed and meets the provided definition of a structure provided.


And, again, I am just arguing to point out the poor wording. I don't think anything except a service needs a ground rod.

 

[Electron_Sam78]

...And, again, I am just arguing to point out the poor wording. I don't think anything except a service needs a ground rod.

Why do you think that?

 

[220/221]

Why do you think that?

Good question but I don't have an educated answer.

On the supply side, the grounded conductor is connected to grounding electrodes at different places like utility poles and pad mounted transformers. It is also connectect at the service.

Whatever it's function is lightning protection/diversion or ground fault potential, that just seems like enough.

 

[Electron_Sam78]

It's obviously intended for protection of equipment from high voltage contact such as lighting strikes. I think the reason behind the code is that you'd want to remove the hundreds of thousands of volts from the equipment and associated circuits as quickly as possible. If it has to travel let's say a 1/4 mile to the closest earth connection then the time it takes to get there is all the more time it has to damage wire, insulation, components. Granted we're talking fractional seconds but at that high voltage every milisecond counts when clearing.