Meter stack grounding

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hhsting

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Please all response NEC 2014.

Attached sketch show 4 position meter stack with terminal box one enclosure. Two meters with 200A breakers are on right and two meters with 200A breakers are on left. Sketch has following:

1. I have neutral bar #1 , equipment grounding conductor bar # 1 on right with neutral to ground bond

2. neutral bar #2, equipment grounding conductor bar #2 on left with neutral to find bond

3. neutral bar on terminal box incoming utility

4. Main grounding electrode system connection is made on the right only shown on sketch ground symbol.

The incoming utility service conductors land on neutral bar then connect to right and left neutral bars as shown.
I have two neutral to ground bond one left and one right.
Have the following questions:

1. How do you size neutral to ground bond based which incoming conductors?

2. Can you have two neutral to ground bonds as shown? Is it in compliance with NEC 2014 Section 250? I did see exception 250.24(B) NEC 2014 to have one overall but not sure if you can have two each side as shown for two meters 200A bkrs each side as shown.
 

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LarryFine

LarryFine

Master Electrician Electric Contractor Richmond VA
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Henrico County, VA
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Electrical Contractor
I believe the bonding and electrode connections should be made in the center section, and based on incoming conductors.
 
GeorgeB

GeorgeB

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I doubt his PoCo allows access to their unmetered service conductor compartment? But I'm not an electrician so should stay out of this thread, sorry.
 
H

hhsting

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electrofelon said:
Have you seen the actual equipment or are you just looking at a sketch? I suspect that the exact layout has not been accurately described to you.
Click to expand...
I am looking at sketch on plans not the actual equipment. How is actual equipment not described accurately? See attached clear sketch.
 

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electrofelon

electrofelon

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hhsting said:
I am looking at sketch on plans not the actual equipment. How is actual equipment not described accurately? See attached clear sketch.
Click to expand...

I am skeptical that there are multiple MBJ's, and that they would be field made and installed. I would suspect that either the equipment is "suitable only for use as service equipment" meaning neutral is factory bonded, or the bond is a single screw or strap. Perhaps you have some odd duck there but its nothing 'i have ever seen. (yes using the "I havent seen it therefore it must not exist fallacy ;))
 
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hhsting

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Hv&Lv said:
View attachment 2551444

is this something like your looking at?
Click to expand...

See attached 6 gang meter stack 3 on each side. I don’t have that. Sketch is similar to 6 gang meter stack except instead of 6 I have 4 gang meter stack 2 on each side. They just come one vertical 4 from all manufacturer. Are you saying 4 gang don’t come in configuration 2 on each side with center stack in between from any manufacturer shown post #1 sketch?
 

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Hv&Lv

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Hv&Lv

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Apparently not. Plenty of five meter, one for common area service.
 
H

hhsting

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electrofelon said:
I am skeptical that there are multiple MBJ's, and that they would be field made and installed. I would suspect that either the equipment is "suitable only for use as service equipment" meaning neutral is factory bonded, or the bond is a single screw or strap. Perhaps you have some odd duck there but its nothing 'i have ever seen. (yes using the "I havent seen it therefore it must not exist fallacy ;))
Click to expand...

Says the neutral bars and equipment ground bars are connected to can at factory not sure how but then it also shows wire between neutral and equipment ground bar each side.

I don’t know what that means but if bars neutral and EGC bar are bonded to can would not wire connect be redundant?

Let’s assume that. neutral to ground bond is factory bonded from manufacturer can the factory neutral to ground bond exist on each side?


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LarryFine

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
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More like this, except 2 x 2 instead of 1 x 5. I've always thought the terminal cabinet was ridiculously large.

DSC00295.JPG
 
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LarryFine

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
hhsting said:
Can you do two separate 2 gang meter breakers on each side with terminal box in between?
Click to expand...
Yes. The whole system is set up to connect together. Each cabinet has a plate on both sides that expose the ends of buses that overlap and bolt together. You can join many sections in various combinations. Note the left side of my pic above.
 
H

hhsting

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Hv&Lv said:

this? Seems to be what I’m understanding.

its like the last one but with provisions for (4) 200 amp breakers
Click to expand...

Yea like that except yours is side ways I have on top of each other.

Back to post #1 sketch. How does one do MBJ and neutral to ground bond something with center stack 4 gang meter breakers 2 on each side?


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H

hhsting

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Something similar to post #1: Attached meter bank has two neutrals its six gang three meter and breakers each side with neutral and equipment bars each side. Let’s say incoming service cable are coming into center box and land on where it says line lugs.

Questions:

1. Would their be two neutral to equipment ground bonds each side?

2. Would #1 be wire neutral to bond? Sized on what conductors?

3. Where would the GEC to Grounding electrode system be? One on each neutral bar?



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H

hhsting

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electrofelon said:
the electrician installing it will know what to do
Click to expand...

alright but drawing sketch from plans on post #1 shows similar situation to post #18 and my questions on 6 gang meter post #18 were basically going back to the wiring on post #1. Can anyone please help with post #18 questions? 250.24 allow either one overall MBJ for assembly or each service disco have its own MBJ but post #18 case has manufacturer provided two neutral bars and two EGC bars on ether side for 3 service disco either side one enclosed assembly.


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