Re: Checking on electric contractor; adjacent sub-panel question



pin_wolf@xxxxxxxxx wrote:
A contractor had to put in a sub-panel in my home because the main box
was full.  I have a few questions on what he did that I hope some
experienced electricians can answer.

The new sub-panel is located immediately (about 4") below the main
panel and connected to it with metal conduit.  To feed the sub-panel,
two existing circuits were removed (and replaced by a dual-pole
breaker) and those existing circuits were extended to breakers in the
sub-panel.

My questions:

1 - Do the neutral and ground need to be separated in this sub-panel?
He bonded them.  Most info in the NEC talks about sub-panels in
separate buildings or at remote locations.  I don't know if the
situation changes if the sub-panel is located so closely to the main
panel.

2 - The hot wires for the moved circuits were extended into the
sub-panel.  Do the neutral and ground wires need to be extended also?
He left them in the main panel and only extended the hot wire.


#1 and #2 are both wrong, but they are also perfectly safe in my opinion (assuming that conduit connecting the 2 boxes is a rigid or IMC conduit and has threaded locknuts.) The new box is supposed be wired as a subpanel. I'm not sure that I would change it though. What did the electrical inspector say?


3 - Given that 2 20A furnace branch circuits (A/C operation and
_electric_ heat) were what was moved, and two additional 20A (patio and
landscape lighting & power) branch circuits added, what is a suitable
breaker to feed the sub-panel?  He put in a 25A and wired the sub-panel
with #10 wire, which seems a bit light considering the 2 furnace
(heater) circuits.

I would have used #6 copper wire and a 50A or 60A breaker. I wonder where he found a 25A breaker instead of a 30.


-Bob
.



Relevant Pages

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