Residential Service Entrance

[Artemis]

I am replacing two panels in a basement of an an existing apartment building. I am replacing the panels with a 200 amp circuit breaker and then relocating the panels inside the individual apartments. Can I use service entrance cable per table 310 .15 (B) (6) from the circuit breaker to the panel inside the building?
Thanks in advance for any help.

 

[John120/240]

Why ??? That sounds like a royal pain to move both apartments circuits

upstairs. You will need 4 conductors to serve these new sub panels.

310-15(b)(6) states for 3 wire service. Some body please clarify for the both

of us.

 

[Artemis]

The occupants of the apartments do not have access to the panels where they are located now and the local AHJ required them to be located in their respective apartments.

 

[wirenut1980]

4 wire feeders are required from the 200 amp breaker to the apartments, since the 200 amp breaker is now the first disconnecting means.

 

[augie47]

Now.. back to your question...
310.15(B))67) states:
(6) 120/240-Volt, 3-Wire, Single-Phase Dwelling Services and Feeders. For individual dwelling units of one-family, two-family, and multifamily dwellings, conductors, as listed in Table 310.15(B)(6), shall be permitted as 120/240-volt, 3-wire, single-phase service-entrance conductors,
so, if your service is 120/240 volt 3 wire and your apartments meet the definition of a dwelling unit, you can apply the Table.

 

[John120/240]

OK so you can apply table 310-15(b)(6), but you still need 4 conductors

correct. So we use 310-15(b)(6) by default because the fourth conductor

doesn't affect the rating ?

 

[wirenut1980]

Thanks Augie. It was lost on me that the OP was asking about the table. :ashamed1:

John, you got it. The 4th wire is an equipment grounding conductor (EGC), which is not supposed to be a current carrying conductor, except under fault conditions.

 

[Little Bill]

OK so you can apply table 310-15(b)(6), but you still need 4 conductors

correct. So we use 310-15(b)(6) by default because the fourth conductor

doesn't affect the rating ?

You can use the table because the new subs will carry the full load to the dwelling. If you left some of the loads at the main and then ran a sub, you wouldn't be able to use the table. You would then need to use 310.16 (2005) or what ever the new number for that table is.