Duplex breaker question

[cbass]

As im reading through the recent ASHI reporter i came up with a few questions that i figured you guys could help me out with. I have a 100 cutler hammer panel model number ch22ccm100, there are 24 total breaker slots including the two for the main breaker. The formula in the reporter says amps x poles divided by 10 (so i would have a total of 20 breakers according to this formula). However the model number above suggests that 22 total slots can be used. The attached picture is of the remaining slots (2) in this panel. These appear to be notched suggesting the allowance of additional tandem breakers? There is no diagram or information dictating the total number of circuits allowed. The other question i have is, how can you determine if the panel is class CTL? Please advise. I appreciate it.

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[randynavarro]

I betcha Reuben would be able to answer you straight-a-way on the ASHI Forum.

I don't think he hangs out here--I can't recall.

Of course, I'm sure there are numerous other qualified folks here to help out--I'm not one of them when it comes to that question!

[Jim Port]

I would trust the manufacturer to know how many breakers can be installed. Typically the model number has the number of breaker allowed in it. The 22 should be correct, with no tandems.

A model number like 3040 would indicate that tandems could be used.

The label inside the panel should have the information you need like CTL and the number of poles allowed.

[Jim Katen]

As im reading through the recent ASHI reporter i came up with a few questions that i figured you guys could help me out with. I have a 100 cutler hammer panel model number ch22ccm100, there are 24 total breaker slots including the two for the main breaker. The formula in the reporter says amps x poles divided by 10 (so i would have a total of 20 breakers according to this formula). However the model number above suggests that 22 total slots can be used. The attached picture is of the remaining slots (2) in this panel. These appear to be notched suggesting the allowance of additional tandem breakers? There is no diagram or information dictating the total number of circuits allowed. The other question i have is, how can you determine if the panel is class CTL? Please advise. I appreciate it.

If there aren't any tandems in there and 22 full-size breakers will fit, I wouldn't get to worked up about it. As Jim Port pointed out, the manufacturer isn't about to manufacture a panel and get it listed by UL if it allows you to simply stick in too many full-size breakers.

Now, if there were tandems in there, I'd look at it more carefully.

As for the CTL panel thing, there should be a sticker inside the panel that says, "CTL Panel."

- Jim Katen, Oregon

[plummen]

20 full size breakers

[hausdok]

Plummen,

Want to tell us how you came to that figure or are we supposed to try and read your thoughts?

ONE TEAM - ONE FIGHT!!!

Mike

[inspectorreuben]

cbass - how old is this panel? If it's a newer panel, the old formula for the maximum number of circuits in a class CTL panel wouldn't apply.

If you don't count the main breaker, and I'm sure you're not supposed to, you'd get 22 branch circuits out of this panel, which would match up with the model number.

I'm quite certain this panel isn't designed for tandems, but I can't tell from the photo.

- Reuben

[plummen]

Plummen,

Want to tell us how you came to that figure or are we supposed to try and read your thoughts?

ONE TEAM - ONE FIGHT!!!

Mike

Those bottem 2 slots are not for breakers,I personally have never seen a panel that takes 22 breakers.

20-30 spaces are common panel layouts for most brands

[plummen]

Well it looks like I not only stepped in it,I also rolled in it! [:-paperba

I just checked ch's site and they list a 22 space and 42 space panel! [:-bigeyes