Bare Grounded conductor to service equipment- White tape? 230.41

Status
Not open for further replies.
E

Earl Olson

Member
Location
Minnesota
I have a situation set up like this: 480v 3 phase 200 amp service. In the conduit from the power company's transformer, there are three 250 AL wires and a bare #4 copper. These enter a CT cabinet, then continue to a 200A service disconnect. Currently, the bare wire is bonded to the CT cabinet, and also to the main disconnect switch enclosure. So there is presently no grounded conductor installed. The load does not require a grounded conductor, (neutral) but the NEC codebook does.

Is there a way to make this legal without pulling another wire? For example: take the bare #4, land it in the CT as if it were the grounded conductor, (230.41) then bond the can, continue into the disconnect, land it on a neutral bar kit and bond the enclosure. I know you can use a bare wire for the grounded conductor, but then should it have white or gray tape to identify it as the grounded conductor?

Thanks guys.
 
Is this underground?

III. Underground Service Conductors
230.30 Installation.
(A) Insulation. Underground service conductors shall be
insulated for the applied voltage.
Exception: A grounded conductor shall be permitted to be
uninsulated as follows:
(1) Bare copper used in a raceway
(2) Bare copper for direct burial where bare copper is
judged to be suitable for the soil conditions
(3) Bare copper for direct burial without regard to soil
conditions where part of a cable assembly identified for
underground use
(4) Aluminum or copper-clad aluminum without individual
insulation or covering where part of a cable assembly
identified for underground use in a raceway or for di-
rect burial
Click to expand...
 
Earl Olson said:
I have a situation set up like this: 480v 3 phase 200 amp service. In the conduit from the power company's transformer, there are three 250 AL wires and a bare #4 copper. These enter a CT cabinet, then continue to a 200A service disconnect. Currently, the bare wire is bonded to the CT cabinet, and also to the main disconnect switch enclosure. So there is presently no grounded conductor installed. The load does not require a grounded conductor, (neutral) but the NEC codebook does.

Is there a way to make this legal without pulling another wire? For example: take the bare #4, land it in the CT as if it were the grounded conductor, (230.41) then bond the can, continue into the disconnect, land it on a neutral bar kit and bond the enclosure. I know you can use a bare wire for the grounded conductor, but then should it have white or gray tape to identify it as the grounded conductor?

Thanks guys.
Click to expand...

I am assuming this is a 480/277 grounded Y service? If you have no line to neutral load then the grounded conductor must be sized per Table 250.102(C)(1) as a minimum. Your #4 meets that requirement. 230.41 allows the use of a bare grounded conductor. Assuming you have all the metallic parts on the line side of the disconnect bonded per 250.92 to the this bare grounded conductor I don't see an issue here.
As for taping it white at the terminations, that would be the correct thing in my view.
 
texie said:
I am assuming this is a 480/277 grounded Y service? If you have no line to neutral load then the grounded conductor must be sized per Table 250.102(C)(1) as a minimum. Your #4 meets that requirement. 230.41 allows the use of a bare grounded conductor. Assuming you have all the metallic parts on the line side of the disconnect bonded per 250.92 to the this bare grounded conductor I don't see an issue here.
As for taping it white at the terminations, that would be the correct thing in my view.
Click to expand...
I have never seen anyone put white tape on the bare grounded conductor when using SE cable as service conductors. I suppose some inspectors would want to see white tape though.
 
Status
Not open for further replies.
Top