Sorry if this is an overpost. Pulling 120 volts from a 240 breaker

[Paul Kondzich]

Sorry if some of you have read this, I posted earlier and checked and it was not in new posts anymore, but had not had responses. The question is I inspected a small 1940s cabin today. There is a "newer" service from the utility with a "newer" service panel. There is a 100 AMP main disconnect (I assume) it is not labeled. The only other breaker in this panel (yes it it the only one) is a 30 amp double pole breaker. The cabin only has 110 volt service inside (gas heat, water heater, stove.) The #10 wire from that 30 amp 2 pole breaker is only using 1 pole of that breaker, and the other wire is going to the grounding bar (only 2 wires.) I could not determine where the newer wire joined with the older cloth covered wire in the cabin. That #10 wire is powering the whole cabin. I remember seeing something on here about if you dont utilize both poles of a two pole breaker it is useless because for a two pole breaker to work it has to sense a difference in the two poles to function correctly?? Anyway any wording help and why its wrong. Also would this be considered 15 or 30 amp service, or would the breaker never trip because only one leg is being used.

[Richard Moore]

OK...I don't really want to touch what is happening inside the cabin, beyond the 30-amp breaker, although it looks like the neutral is incorrectly labeled with green tape. Could there be a sub-panel or fuse-box inside, grounded by the metal conduit?

Anyway...sticking to your questions...

The 30-amp double pole will trip just fine (at 30+ amps) with only one side used. It's just two separate breakers with a mechanical exterior link. The handle tie will mechanically trip the other, but one side or pole doesn't "know" or "care" what the other is doing.

I don't know what the panel itself is rated for, but I'd call that a 100-amp service, barely used. The back-fed main breaker is rated 100-amp and the feeders look big enough. That back-fed main, BTW, should have a retaining device.

[Jerry Peck]

Paul,

See if this helps: http://www.inspectionnews.net/home_inspection/electrical-systems-home-inspection-commercial-inspection/7386-power-both-buss-bars.html

[Erby Crofutt]

Just a note for you, Paul, on your first post not showing up on "new posts".

You'd already read it therefore it was not a "new post" to you. It still showed up to others, who had not signed in since you posted it, as a "new post".

It was still there in the forum you posted it in.

It won't show up in the "new posts" for you, until someone posts a response to it.

[Jerry Peck]

Adding to what Erby said, if the post gets to be too old and others have read it and not responded, you can always just reply to your own post, typically with "Bump" as your message and it "bumps" the thread back up as a new un-read thread.

Saves having to make duplicate posts.

[Randy Clayton]

Paul, from your post and pic;I can only determine that this cabin was on a 110v circuit. that there is no 220v serv. required. Forget about that two pole thing you where saying;if the breaker bar should have been removed if the 220v was not required..