Service panel - can I use these slots?


Old 10-22-18, 04:06 PM
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Service panel - can I use these slots?

Hi all, new guy here, nice to meet everyone.

So, I'm looking at my main service panel for a place to put in a 125A breaker for a new subpanel. Fig 1 shows the overall breaker layout (apologies if pics are sideways; if you're seeing them in landscape orientation, "up" is to the left).

The only two adjacent open spaces are at the top, as you can see in fig2. Those are connected to two hot lines coming in from the meter side of the enclosure, 240V across them. They aren't connected to the main bus bars or anything else as far as I can tell. The front panel knockouts are still in place and labeled "service disconnect," which is not true. The actual service disconnect is the 200A 4-pole breaker in fig3.

I'm a hesitant to just go ahead and connect a 125A breaker to those open slots (even though it would fit), because those lines from the meter side might not be large enough to handle 125A (I can't tell what size they are or what kind of insulation they have), and also because they don't seem normal. However, I could move a smaller, 20A, breaker up to one of the slots, which would free up two adjacent normal slots for my 125A breaker.

I'm hoping someone who has seen older panels like this can explain the situation to me and give me an idea if using those weird slots is legal. I am planning to have the subpanel installation inspected and permitted. For reference, it is a Square D panel of some sort, that happens to fit Square D Homeline breakers. Except for the brand, none of the labeling is readable.

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Last edited by PJmax; 10-22-18 at 07:46 PM. Reason: resized, reoriented pics
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Old 10-22-18, 06:34 PM
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I believe you are going to need to use two spaces.with nothing else on the stabs, if you can even install a 125 amp breaker. The issue is going to be the bus stab ratings.
Old 10-22-18, 07:50 PM
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Interesting set up with the quad breaker handle tie. Is that the main ?
I've never seen that in a meter/panel combo.
Old 10-22-18, 10:12 PM
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pcboss, thanks, yeah, I think that's going to be my problem -- it's going to be tough to find ratings.

pjmax, yep, the quad breaker is the main. Odd duck. Thanks for fixing the pics!
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