Weird SQ D Non CTL thing

[Birken Vogt]

The reason QO specifically would say non-CTL tandems to be used is that a few years back they changed their clip rail that the bottom part of the breaker clips onto. It used to be a round thingy, that breakers clipped onto. In CTL spaces they put a slot through it for these weird hooks. In recent times they have changed the round rail from plastic to metal so it becomes a PON neutral bus bar for modern full size scam breakers to clip onto. Well that seems to have done away with the space for the hook so now if you want tandems you have to buy non-CTL. Of course the non-CTL cost way more than the standard tandems. The whole system is broken in disarray.

 

[electrofelon]

The reason QO specifically would say non-CTL tandems to be used is that a few years back they changed their clip rail that the bottom part of the breaker clips onto. It used to be a round thingy, that breakers clipped onto. In CTL spaces they put a slot through it for these weird hooks. In recent times they have changed the round rail from plastic to metal so it becomes a PON neutral bus bar for modern full size scam breakers to clip onto. Well that seems to have done away with the space for the hook so now if you want tandems you have to buy non-CTL. Of course the non-CTL cost way more than the standard tandems. The whole system is broken in disarray.

Oh interesting, that makes sense that they were in a bind when they wanted to go to plug on neutral, wasn't compatible with their CTL breakers

 

[James L]

Makes good sense to me for QO

 

[kwired]

Oh interesting, that makes sense that they were in a bind when they wanted to go to plug on neutral, wasn't compatible with their CTL breakers

I didn't think of the PON either, yet it doesn't really make sense anymore to have a 20/24 panel either, why not 20/40?

 

[James L]

I didn't think of the PON either, yet it doesn't really make sense anymore to have a 20/24 panel either, why not 20/40?

Right. They all stab on the same.
The only difference between 24 and 40 circuits is the nomenclature saying it?

 

[LarryFine]

The real question is why are non-CTL breakers more expensive?

Because they know they're all that will fit in non-CTL panels, and people will pay more for them.

 

[jim dungar]

I didn't think of the PON either, yet it doesn't really make sense anymore to have a 20/24 panel either, why not 20/40?

Most likely heat rise testing for the UL listing. I don't know what branch breakers and loading are used during this test.

 

[kwired]

Most likely heat rise testing for the UL listing. I don't know what branch breakers and loading are used during this test.

Makes sense until you run into 42/84 panels of same design.

Before the 42 circuit rule disappeared things like 30/40 panels were pretty common. Now a majority of them accept tandems in every slot.

But the plug on neutral design of QO presents an issue I never thought of before.