repost ground bushing conductor size other req

[hhsting]

Sorry to repost but have following questions not sure why other thread closed

I have 208/120V three phase system

questions:


1. For downstream of service equipment FEEDER conduit ground bushing is used. The conductor sizing from ground bus to the ground bushing is confusing for feeder conduit. Previous post just says (C) or (D). Its not clear. We use Table 250.102(C)(1) or Table 250.120(D) for bond conductor size feeder conduit?

2. Where does it state in NEC 2014 other options or requirement besides ground bushing for 208/120V three phase system Feeder conduit?

 

[Greentagger]

250.122

 

[electrofelon]

Read ALL OF 250.92, 250.96, and 250.97. Next note that 250.96 is the one that applies to a 208 feeder. Note it DOES NOT SAY a grounding bushing is required or other such means that ARE required in 250.92 and 250.97. A typical fitting with a lock not is all that is required. It DOESN'T SAY you need to use grounding bushing so you don't have to, bit you can of you want.

 

[hhsting]

Read ALL OF 250.92, 250.96, and 250.97. Next note that 250.96 is the one that applies to a 208 feeder. Note it DOES NOT SAY a grounding bushing is required or other such means that ARE required in 250.92 and 250.97. A typical fitting with a lock not is all that is required. It DOESN'T SAY you need to use grounding bushing so you don't have to, bit you can of you want.

NEC 2014 Section 250.96 (A) says if used as EGC it needs to be bonded. In my case its NOT used as EGC and they are feeder conduit for 208/120V.250.96(B) is about isolated ground.

I see that 250.97 says for over 250V to ground for other than service conductor.

If grounding bushing is not required 208V feeder conduit then Is their any requirement for less than 250V ground for other than service conductors for electrical continuity of metallic conduit other than service conductors Less than 250V if not used as EGC? What section are they in?

 

[roger]

You have been given the answers, you will need to read the article sections.

Roger