Service trough, conduits grounding

[hhsting]

Please see attached sketch. I have 480/277V three phase incoming electric utility service conductors into trough 3 sets of 4#600kcmil. From trough there are three connections in metallic conduit to three service disconnects.

From trough to SVRC#1: Fused at 400A incoming I have 3#500kcmil phase conductors + 1#500 kcmil neutral

From trough to SVRC#2: Fused at 200A incoming I have 3#3/0Awg phase conductors + 1#3/0 Awg neutral

From trough to SVR#3: Fused at 600A incoming I have 3 sets of 3#3/0 phase conductors + 1#3/0 neutral

Question:

1. Since their is no equipment groundconductor coming in line side of fused disconnects how would the wireway, metallic conduit between trough and service disco and service disconnects themself be grounded and bonded? They are metallic.

2. Would the same question as number #1 however the incoming utility voltage is 208/120V three phase?

 

[tom baker]

How is a meter enclosure, which is ahead of the service disconnect, bonded? Hint: Look in Article 250 for a section on use of the grounded circuit conductor for grounding equipment.

 

[hhsting]

How is a meter enclosure, which is ahead of the service disconnect, bonded? Hint: Look in Article 250 for a section on use of the grounded circuit conductor for grounding equipment.

Ok so I think it’s either NEC 2014 sections 250.80, 250.92(A)(B) but I am not sure which one exactly post #1??? Can you please help exactly which one or some other section in 250?

 

[hhsting]

Ok so I think it’s either NEC 2014 sections 250.80, 250.92(A)(B) but I am not sure which one exactly post #1??? Can you please help exactly which one or some other section in 250?

I guess I failed it. Sorry for my ignorance. I guess this might probably end like other thread no one willing to help or answer further. Where is my buddy Electrofelon?

 

[texie]

I guess I failed it. Sorry for my ignorance. I guess this might probably end like other thread no one willing to help or answer further. Where is my buddy Electrofelon?

I would suggest you purchase a copy of Soares Grounding and Bonding. It is an excellent reference book with lots of very good illustrations. It will help you immensely. Amazon or IAEI will have it.
You get points for finding 250.80 and 250.92. There a number of illustrations is this book that illustrate this very well.

 

[electrofelon]

I guess I failed it. Sorry for my ignorance. I guess this might probably end like other thread no one willing to help or answer further. Where is my buddy Electrofelon?

You got it in post #4. 250.80 is saying connect "service stuff" to the grounded conductor. 250.92 is saying what and how to bond everything together. Its logically a bit redundant yes.

In practice, there are several ways to do it. I would probably use bonding locknuts at the nipples into the trough. The bottom of the nipples would be in a threaded up so that complies. Another way would be to run a SSBJ from the disco(s) to bond the trough, however the code does not say how to run SSBJ's with multiple service disconnect enclosures.

 

[hhsting]

You got it in post #4. 250.80 is saying connect "service stuff" to the grounded conductor. 250.92 is saying what and how to bond everything together. Its logically a bit redundant yes.

In practice, there are several ways to do it. I would probably use bonding locknuts at the nipples into the trough. The bottom of the nipples would be in a threaded up so that complies. Another way would be to run a SSBJ from the disco(s) to bond the trough, however the code does not say how to run SSBJ's with multiple service disconnect enclosures.

Electrofelon my buddy thank you and also thank you to texie and Tom Baker. Your responses and input greatly appreciated