120V Subpanel?

[davedottcom]

Re: 120V Subpanel?

Originally posted by georgestolz:
]It would need to be secured as a backfed device, per (NEC-2002) 408.16(F).

 

[George Stolz]

Re: 120V Subpanel?

Originally posted by davedottcom:
you could just use a single pole breaker on the A Phase and run a jumper from the breaker to the feed the B phase lug!

That's true. It would probably wind up being a 2-pole with one phase not in use, in this case. I don't believe I've run across a 1 pole 50 amp breaker.

 

[tshea]

Re: 120V Subpanel?

I don't believe I've run across a 1 pole 50 amp breaker.

Square D makes a QO130, QO140, QO150, QO160.

 

[LarryFine]

Re: 120V Subpanel?

With a #6 feeder, 60a, a single-pole 30 should be able to carry half the panel okay.

 

[don_resqcapt19]

Re: 120V Subpanel?

Dave,

That's easy enough, and if it's not possible for some reason you could just use a single pole breaker on the A Phase and run a jumper from the breaker to the feed the B phase lug!
That's NOT back feeding!

Why is that not backfeeding? The feed would be landed on the breaker and the breaker snapped onto the bus.
Don

 

[davedottcom]

Re: 120V Subpanel?

Don, it just isn't!
The single SE ungrounded conductor would be terminated to the A phase lug energizing all of the A phase bars. The breaker would be attached to the A phase just like all the other breakers. A "jumper" wire would run from the breaker "load" terminal to the main "line" lug of phase B. When you would turn on that breaker it would energize the main B lug and the rest of the B phase bar. Same 120 volt feed into both phases. The single pole breaker in the main panel would control both A & B phases in the sub panel.

In short, the breaker would be energized from the phase bar not the screw terminal, therefore it's not getting back-fed.

 

[don_resqcapt19]

Re: 120V Subpanel?

Dave,
I didn't catch how you were making the feeder connection. sorry
Don

 

[jim sutton]

Re: 120V Subpanel?

Dave: you have some imagination!

 

[davedottcom]

Re: 120V Subpanel?

Originally posted by jim sutton:
Dave: you have some imagination!

 

[benaround]

Re: 120V Subpanel?

Well, I guess that install is up to code!!! I wonder how that makes you feel?

frank

 

[davedottcom]

Re: 120V Subpanel?

Originally posted by benaround:
Well, I guess that install is up to code!!! I wonder how that makes you feel?

frank

mixed feelings I guess...

5%


Yep, that pretty much sums it up!

 

[tshea]

Re: 120V Subpanel?

Is it Wed yet? What did you find? Uh uh??

 

[jeff43222]

Re: 120V Subpanel?

Somebody sounds a little impatient...

I'm meeting the homeowner tomorrow at 3:00 pm to size up the situation. I'll be sure to report back afterward and let you all know what I found.

 

[George Stolz]

Re: 120V Subpanel?

Originally posted by davedottcom:
mixed feelings I guess...

You forgot one other constituency:

1%

 

[allenwayne]

Re: 120V Subpanel?

Just post a label 120 volt sub panel only,if they go to hook up a 240 welder well they are csrpenters doing brain surgery

 

[jeff43222]

Re: 120V Subpanel?

I went and looked at it today. It was pretty much what I expected -- DIY hack job. Someone thought protecting a 12/3 cable with a 30A breaker was a good idea. Lots of NM is also stapled up very poorly on wall surfaces.

In the basement of the duplex (two separate services) I found an interesting multiwire circuit. One leg of the circuit was fed from a breaker in one main panel, and the other leg was fed from a breaker in the other main panel. For some reason, the hot from the circuit in panel #1 was connected to an outgoing hot in panel #2 via a length of 12/2 between the two panels. The neutrals in the NM were not used. I have no idea why anyone would wire something up like that. I didn't have my DMM with me, so I don't know if the two circuits were on opposite phases.

All in all, it's not a job I really want, so I'm going to bid it high.