How many tandem breakers?

[Mikf44]

I have a 22 space 150 amp Square D breaker panel. How many tandem breakers can I put in it? There are already 4 in it.

Thanks

ETA I looked on the label in the panel and it did not say. I also tried looking on the web site and could not find anything.

 

[lametec]

What's the panel part number?

If it's something like XX22-30XYZ, then it's a 22 space panel that can hold up to 30 breakers, meaning 8 of the 22 breakers can be tandem breakers.

 

[Mikf44]

The only number I could find was QOC20U

Its is a 20 space panel not a 22 like I said originally.

 

[lametec]

QOC20U is the cover part #. The panel part # should be on a sticker on the panel. This label might be on the inside of the box, requiring removal of the front panel.

 

[Mikf44]

I don't see any numbers. Could it be behind the cover?

 

[lametec]

Could be, yes.

Look for something along the lines of QO120-30M150, meaning it's a 150A capacity panel with 20 spaces and a maximum of 30 circuits. 30 circuits - 20 spaces = 10 can be tandem. It could also start with HOM.

 

[Mikf44]

QO20-30M150

So I guess I can have up to 10 tandems.

Thanks a lot.

 

[lametec]

Yep, you got it.