QO twin breakers, two styles ?

[James L]

I'll let you continue arguing semantics.

You're correct. The mention of CTL means it accepts tandems. That relatrs to the whole panel

 

[LarryFine]

I've never seen a panel label that did not correctly identify which spaces would accept tandems.

 

[kwired]

I've never seen a panel label that did not correctly identify which spaces would accept tandems.

You don't install much Square D?

Can't tell you how many QO140M200 panels I have installed over the years. (that is a 40 circuit panel that does not accept tandems, before the 42 circuit rule went away).

The covers never mentioned anything about tandems. The labeling space always had a dotted line down center of each space in case of tandems but it never said they were/were not allowed on the cover.

Some older panels from 60's and 70's might have had more of this detail on the covers, but since they went with the design that is still in use and has been for around 30 years they haven't put anything on the cover labels regarding where you can use a tandem. Any such information when applicable is on the label inside the loadcenter itself. The covers are more generic as they often fit more than one loadcenter.

 

[jim dungar]

Those were made before the CTL requirements were in effect.

The non-CTL QO tandem breakers are still being made.

CTL came out in the 60's so technically the replacement style tandem breakers should only be used in 60 year old. panels.

 

[kwired]

The non-CTL QO tandem breakers are still being made.

CTL came out in the 60's so technically the replacement style tandem breakers should only be used in 60 year old. panels.

Today's non CTL tandems replaced the ones that look like what I posted a picture of in post 10, which were also non CTL, but also befoe CTL existed.

Only external difference of CTL types is the rejection hook. Internally, who knows. They possibly all the same and they charging you an arm and leg to not put the rejection hook on there? This is after all the same group of manufacturers that forced the AFCI's on us, also promised us the first generation AFCI's would do what the combination type supposedly does

 

[James L]

Today's non CTL tandems replaced the ones that look like what I posted a picture of in post 10, which were also non CTL, but also befoe CTL existed.

Only external difference of CTL types is the rejection hook. Internally, who knows. They possibly all the same and they charging you an arm and leg to not put the rejection hook on there? This is after all the same group of manufacturers that forced the AFCI's on us, also promised us the first generation AFCI's would do what the combination type supposedly does

Yes, they charge an arm and a leg for the breakers that don't have the rejection clip. Double, in fact

But that doesn't stop some people from buying the CTL Breakers then popping the rejection clip out with a small screwdriver. I've seen it done

 

[jim dungar]

Today's non CTL tandems replaced the ones that look like what I posted a picture of in post 10, which were also non CTL, but also befoe CTL existed.

No.

CTL was introduced about 60 years ago.

The breaker picture you posted, in #10, is simply an older QO style (end to end) rather than the newer style (side to side) that came out about 30 years ago. The breaker part numbers did not change although the breaker appearance did.

 

[kwired]

No.

CTL was introduced about 60 years ago.

The breaker picture you posted, in #10, is simply an older QO style (end to end) rather than the newer style (side to side) that came out about 30 years ago. The breaker part numbers did not change although the breaker appearance did.

Newer style has to be more than 30 years ago, but maybe less than 40.

I could be wrong on the side by side only being non CTL, though I don't recall ever seeing any that are CTL. Never really seen CTL type in the side by side either until about 20 years ago. Yes most those installs were wrong. Nobody knew it was wrong at the time. When permits/inspections became more commonly required some this stuff started getting pointed out by inspectors and many commonly violated things started to change overall.

 

[James L]

Newer style has to be more than 30 years ago, but maybe less than 40.

I could be wrong on the side by side only being non CTL, though I don't recall ever seeing any that are CTL. Never really seen CTL type in the side by side either until about 20 years ago. Yes most those installs were wrong. Nobody knew it was wrong at the time. When permits/inspections became more commonly required some this stuff started getting pointed out by inspectors and many commonly violated things started to change overall.

I remember seeing QO CTL tandems for the first time in 1993. Side by side, just like the pic

Before that, I had never been in a QO panel.

I couldn't understand why they had that giant hook on the back. All I knew was they wouldn't fit in my sister's panel when I rewired her house.

So I cut the hooks off with my dikes.
It wasn't easy. Those hooks are thick