Are piggy backs allowed in this panel?

[Dsg319]

I’ve got a Siemens PN4040B1200.
Most panels I see have a diagram showing how many and where the piggy backs are allowed.

I assume this panel doesn’t allow any?

 

[kwired]

I don't run into a lot of Siemens but guessing the "4040" in the catalog number means 40 space 40 circuit like it does for nearly all others.

4060, 4080 would mean 40 spaces and 60 or 80 circuits is permitted.

Can also take a look at the bus and see which ones are different to allow the "piggy back" breakers to even be installed. Keep in mind those spaces are intended to accept CTL rated breakers, a non CTL will plug into any space.

 

[jaggedben]

Is 'piggy back' another name for a tandem breaker? Never heard that before.

I find panel diagrams to be hit or miss on this question. I really just look for whether the stabs are notched. I suspect that in this case kwired is correct that since it's sold as a 40/40 you cannot use tandems. In my experience that is prevalent among Siemens 40 space panels.

 

[kwired]

Is 'piggy back' another name for a tandem breaker? Never heard that before.

I find panel diagrams to be hit or miss on this question. I really just look for whether the stabs are notched. I suspect that in this case kwired is correct that since it's sold as a 40/40 you cannot use tandems. In my experience that is prevalent among Siemens 40 space panels.

Again not all that familiar with Siemens, especially what may have changed the last 20 years or so. But most others I have seen allow tandems in all spaces anymore since the NEC removed the 42 circuit limit which I think was in either 2008 or 2011 edition, maybe even 2005.

But then they also expanded AFCI requirements so for dwellings especially you aren't using more than one circuit for one space as a general rule.

 

[infinity]

But most others I have seen allow tandems in all spaces anymore since the NEC removed the 42 circuit limit which I think was in either 2008 or 2011 edition, maybe even 2005.

I have an 40/80 Eaton panel that allows all tandems, even CTL's in all spaces.

 

[kwired]

I have an 40/80 Eaton panel that allows all tandems, even non-CTL's in all spaces.

Non CTL's have always fit in any space.

It sort of a moot thing now a days though other than when dealing with existing panels.

All the Square D panels I have used in past several years have been 20/40, 30/60, 40/80 etc. This seemed to be the trend not long after the 42 circuit limit disappeared from NEC.

 

[infinity]

Non CTL's have always fit in any space.

Yes you're correct, I mean CTL's not non-CTL's. I'll fix it.

 

[Dennis Alwon]

Imo, 4040 means 40 circuits period. No twins, tandems, piggy backs or whatever you call them.

 

[Dsg319]

Appreciate the feed back. Thanks guys.

 

[Jraef]

I don't run into a lot of Siemens but guessing the "4040" in the catalog number means 40 space 40 circuit like it does for nearly all others.

4060, 4080 would mean 40 spaces and 60 or 80 circuits is permitted.

Can also take a look at the bus and see which ones are different to allow the "piggy back" breakers to even be installed. Keep in mind those spaces are intended to accept CTL rated breakers, a non CTL will plug into any space.

Yes, you have interpreted that correctly. "4040" means there are 40 spaces that can accommodate 40 poles maximum, which indirectly means that none of the poles are set up to accept tandem breakers. If the panel were able to accept tandems, the number would be something like 4060, meaning 40 spaces, but up to 60 poles, because 20 of the spaces are capable of accepting tandems.

Using Non-CTL tandems in a CTL panel by the way is technically a Code violation, because those are listed ONLY as "replacement use" in "Non-CTL" panels built before 1965 (when the concept of CTL was added).

 

[letgomywago]

Yes, you have interpreted that correctly. "4040" means there are 40 spaces that can accommodate 40 poles maximum, which indirectly means that none of the poles are set up to accept tandem breakers. If the panel were able to accept tandems, the number would be something like 4060, meaning 40 spaces, but up to 60 poles, because 20 of the spaces are capable of accepting tandems.

Using Non-CTL tandems in a CTL panel by the way is technically a Code violation, because those are listed ONLY as "replacement use" in "Non-CTL" panels built before 1965 (when the concept of CTL was added).

Eaton is trying to change this. They owe us one with the whole afci thing they could help us out if CTL disappeared so long as the breakers don't overload each buss stab

 

[kwired]

Eaton is trying to change this. They owe us one with the whole afci thing they could help us out if CTL disappeared so long as the breakers don't overload each buss stab

I'd expect any such change to only apply to products made after said change. A 1990 built load center still will be limited to what the labeling says.

And today most of the new ones do accept tandems/twins/etc. in every position probably mostly because of NEC dropping the 42 circuit maximum rule.