250.6(B)

[russ]

We currently use the 2000 City of Chicago electrical code. Our city council is going to adopt the 2004 Chicago code.

Neither version allows the use of nonmetallic conduit for the service entrance conduit.


18-27-230.43. Wiring Methods for 600 Volts, Nominal, or Less.
Service-entrance conductors shall be installed in accordance with the applicable requirements of this chapter covering the type of
wiring method used and limited to the following methods:
(1) Rigid metal conduit;
(2) Intermediate metal conduit;
(3) Service-entrance cables for existing residential occupancies of not more than three units;
(4) Busboys;
(5) Cablebus;
(6) Mineral-insulated, metal-sheathed cable.

All the standard meter cans come with the neutral lugs bonded to the can.

250.28 tells us to bond the service grounded conductor to the equipment grounding conductor(s) with the main bonding jumper at the main disconnect

Do you think I should ask them to amend 230.43 to allow non metallic conduit to be used in the portion between the meter and the main disconnect, so that 250.6 can be complied with.

 

[bphgravity]

Re: 250.6(B)

Yes, that would be a good proposal.

 

[don_resqcapt19]

Re: 250.6(B)

The use of metallic service conduit is the most common service installation in this area. Yes, the conduit is in parallel with the grounded conductor, but few if any reported problems from this parallel path.
Don

 

[russ]

Re: 250.6(B)

Bryan:
Thanks for the reply.

I don't see any down side to this proposal.

Does anybody?

 

[ryan_618]

Re: 250.6(B)

This parralel path occurs all of the time, in my opinion. Think of a commercial building. What about the CT can? How can it be bonded with out using the grounded (nuetral) conductor?

 

[russ]

Re: 250.6(B)

Hi Don:

I did have one meter burn up. They had a bad neutral connection in the meter and the breaker panel burned at the locknuts. Granted grounding bushings probably would have helped.

Russ

 

[russ]

Re: 250.6(B)

HI Ryan:

CT cans by me have the neutral isolated from the ground.

 

[russ]

Re: 250.6(B)

In reguards to the CT cans.
I should have added in that case metalic conduit would be required.