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zapped 1

Member
Location
north port fl
good afternoon gentlemen. I have a 400 amp switch feeding up to a trough which then is going to feed a 320 mc and disc switch for unit #1 and also a 200 amp mc and disc switch for unit #2. My question is do u think the nuetral and ground should be together at the 400 amp switch and then seperated at each disco or is the 400 amp considered my first switch. any feedback appreciated or if i did not give enough info please let me know thanks
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
Once you pass thru the main disconnect switch the neutrals and grounds should be separate. They are only bonded together at the service disconnect(s).
 

augie47

Moderator
Staff member
Location
Tennessee
Occupation
State Electrical Inspector (Retired)
Definitely not tied together after your 400 amp switch. As to them being tied together IN the 400 amp switch, it depends on that being the service disconnect (or SDS disconnect or separate building disconnect)....
What is the origin of the feed to the 400 amp switch ?
 

zapped 1

Member
Location
north port fl
the 400 amp is being fed from poco thats why were confused u cannot seperate them before the meter can or in the meter can would u ? to me they should be bonded together at the 400 they then go to the trough hit meters where they are still together and then be seperated at each disco coming off the meter?
 

augie47

Moderator
Staff member
Location
Tennessee
Occupation
State Electrical Inspector (Retired)
The grounded conductor should be bonded to the equipment grounds in your 400 amp service disconnect. Generally there should be no connection between the grounded and grounding past that point (250.24).
250.142(A)(3) does make an exception for meter sockets under specific conditions.
 

Little Bill

Moderator
Staff member
Location
Tennessee NEC:2017
Occupation
Semi-Retired Electrician
The grounded conductor should be bonded to the equipment grounds in your 400 amp service disconnect. Generally there should be no connection between the grounded and grounding past that point (250.24).
250.142(A)(3) does make an exception for meter sockets under specific conditions.

Gus,
Is the article you referenced different in the 08 from the 05? I ask because (don't have my 08 handy) 250.142(B) is where meter enclosures are in the 05.
 

suemarkp

Senior Member
Location
Kent, WA
Occupation
Retired Engineer
Does the 400A switch have an overcurrent device inside it? It is labeled Suitable for use as Service Equipment?
 

kwired

Electron manager
Location
NE Nebraska
My suggestion is to place the two meters and disconnects adjacent to one another if you can and make them the up to 6 allowed main disconnects and not use the 400 amp disconnect. Then you will have no grounding/grounded issues.
 
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