Grounding Site lights

[don_resqcapt19]

Ryan,
I agree that the definition of service point is poor. I think it should be where the ownership of the power changes, but the code doesn't say that. That being said, I agree with Bob, if the transformer is customer owned, then the service point is somewhere on the line side of the transformer.
Don

 

[ryan_618]

OK, so you need to have a disconnect between the primary and the secondary??? As Bob said, you can't have a tranformer on the line side (Which I think is an error in the NEC). I still can't call anything a feeder until it hits a disconnecting means though.

 

[Pierre C Belarge]

I agree with Don in that the conductor may not be sized large enough to conductor the potential fault current... hence the note at Table 250.122.

 

[iwire]

There must be (should be) a customer owned service disconect on the line side of the customers transformer.

On the load side of the transformer the conductors very likely fall under the rules of 240.21(C)(4) until they terminate at a single circuit breaker or a single set of fuses that limit the load to the ampacity of the conductors.

When you read 240.21(C)(4) it seems to mirror many of the requirements for a service.

 

[ryan_618]

I'm not worried about the grounded condcutor, since it must be sized 250.24(C), which includes the 12.5% rule.

What I am worried about is telling the installer/designer/owner to go ahead and purchase a 12,470 Volt 3 phase disconnect that wasn't on the plans!!!

 

[iwire]

What I am worried about is telling the installer/designer/owner to go ahead and purchase a 12,470 Volt 3 phase disconnect that wasn't on the plans!!!

It sucks to be them. :lol:

I see switches of that caliber all the time in Universities, Hospitals, Research facilities and once in a while even in large office buildings.

 

[ryan_618]

It sucks to be them. :lol:

It certainly does. :lol: :twisted: :twisted: :twisted:

 

[davidv]

There are designers that do not bother to clear the issue to the Utility sales people, and leaves it for the project management ,
but not showing a disconnect on the diagram or plans, does speak something for that job

 

[Pierre C Belarge]

There are many times that the engineers may not understand a code issue and are designing as they have been taught... from someone who did it "that way all the time".

I can say that I have had times (personal experience), where I have had to tell the company to make changes even though the drawing said one thing. The argument is that it is "engineered" that way... I even had to go to State mediation on one job, they made the changes. :wink:

I know when big bucks and job schedules are in the way, that the time to tell them to make the correction is not easy. If this is during plan review, I would not hesitate or worry about my battle gear, I would notify them.

 

[benaround]

Bob, (Iwire)

250.32(b)(2) is assuming the disconect is at the seperate structure.

250.32(D) is for remote disconect and I read it as you must bring an

EGC with the circuit conductors. Where am I missing it?

Thanks,

 

[iwire]

Bob, (Iwire)

250.32(b)(2) is assuming the disconect is at the seperate structure.

250.32(D) is for remote disconect and I read it as you must bring an

EGC with the circuit conductors. Where am I missing it?

Thanks,

250.32(D) only comes into play when we use Exception No. 1 or 2 of 225.32

In this case we would not be using either Exception No. 1 or 2 of 225.32 we would be using exception 3 of 225.32 and 250.32(D) does not apply.

 

[benaround]

Bob,

It's just that easy! yesterday I could not get that thru my head, today

it makes perfect sense.

Right turn Clyde!

Thanks,

Frank.