[Joe Momma]

So I took over this job from another guy who did all the underground. There's a main building and 100 yards away sits the CT, Main Disconnect, Transfer switch and Generator.

Now the pad with all the service equipment will have a ground ring and that's what he's going to use for his electrode, which is fine. Except that he wants to put all the elctrodes in the building(ufer, water pipe, and steel) under the ground bus in the MDP.

It all sounds like it will work the same, but I thought for sure that the GEC only lands at the Target and never anywhere else? Shouldn't the building electrodes go out and tie in with the ring and all land in the same spot together? I'm just having a hell of a time finding a refference.

Thanks

 

[JohnJ0906]

Joe, I think that the building would count as a seperate structure from the service, and so would require a grounding electrode system of it's own, seperate from the service. As a matter of fact, you might need a disconnect on the building as well.
Sorry, I'm not home, and don't have a code book handy.

 

[Joe Momma]

You know, the inspector Tuesday also said he thinks I need main within, or on the building. I went through my submittals and the MDP says it has main lugs only.

He couldnt remember the refference(combo inspector), and passed me off for the time being, I imagine it will come up again for the power to panel inspection.

 

[JohnJ0906]

Do you have 6 breakers or less?

At 100 yards from service to buildings, I don't see how a disconnect wouldn't be required, IMHO 225.31

What I would consider this is 2 structures. Building, and service.

Out of curiosity, why the separation?

 

[raider1]

You do have 2 structures and will need a disconnecting means at the building. (See 225.31)

Also the GEC at the building needs to be connected to the EGC terminal at the disconnecting means of the building.(See 250.32(A))

Are you bringing an EGC with the feeders from the service equipment to the MDP at the building?

Chris

 

[Joe Momma]

225.31 Disconnecting Means
Means shall be provided for disconnecting all ungrounded conductors that supply or pass​

through the building or structure.

There is a disconnecting means, just not within the building. And yes there are more than 6 motions of the hand in the MDP.

There is, of course, an EGC coming in from where the grounding conductor was created(bullseye).

The seperation, is due to convenience of where to set the utility xfmr and gen-set.

About this 'seperate building/structure' issue, does NEC have a definition?


EDIT:
I just read on after .31 to.32 exception 1

225.32 Location
The disconnecting means shall be installed either inside or outside of the building or
structure served or where the conductors pass through the building or structure. The
disconnecting means shall be at a readily accessible location nearest the point of entrance
of the conductors. For the purposes of this section, the requirements in 230.6 shall be
utilized.
Exception No. 1: For installations under single management, where documented safe
switching procedures are established and maintained for disconnection, and where the
installation is monitored by qualified individuals, the disconnecting means shall be​

permitted to be located elsewhere on the premises.

And think I may still have a leg to stand on, but then again; anyone that knows me in here knows I'd rather fight than conceide

 

[JohnJ0906]

"Structure" : That which is built or constucted. (NEC definition)

IMHO, the building needs a seperate GE system, as well as an EGC from the MDP.

You MAY be able to use the exception to 225.32, but you can judge that better than we can, I think. Of course, the AHJ might have a say as well! :whistling2:

 

[Joe Momma]

At 100 yards from service to buildings, I don't see how a disconnect wouldn't be required

"Structure" : That which is built or constucted. (NEC definition)

I was wanting to know the definition of "seperate" structure, for some reason I assumed your first quote above had something to do with why it is called 'seperate'

Anyway,
a different inspector(friend of a guy on the job) says we do not need a disconnect nearest to where the conductors enter the building.
He says all that is needed is a label on the indoor gear saying the main disconnect is out in the parking lot.
The only article I found to explain this is 225.37.

I suppose it's a matter of interpretation, but any input would be appreciated.

 

[raider1]

Hey Joe Momma,

The inspector friend of the guy on the job, is wrong. The building in question is 100 feet away from the service, so it is a separate structure that is fed by a feeder. 225.31 requires that a building that is fed with by a feeder or branch circuit have a disconnecting means installed either outside or inside nearest the point where the feeder enters the building.

The section that he uses 225.37 just states that when more than one feeder, branch circuit or service feed or pass through a building, then a permanent plaque or directory needs to be installed at each feeder, branch circuit or service disconnecting means location denoting all other services, feeders or branch circuits supplying or passing through the building or structure. This section does not eliminate the need for a disconnecting means at the building or structure.

Chris

 

[Joe Momma]

Thanks for the help Chris, there are some things in the code that are sometimes forgotten or overlooked, but I'm having a very tough time accepting what my shop wants to do with something as important as disconnecting power. And why; to save money on something they overlooked when drawing their own prints.

The handbook had some notes on article 225.37 that sent me to article 702 where I read on to 702.11, which also states that this installation is a violation and does not have any exceptions.

 

[raider1]

Your welcome.

Chris