QT Breakers
#1
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QT Breakers
Where do I find if a QT breaker is rated for a G2020MB1100 panel? The panel is 20 years old and the QT breaker physically installs into the panel but how do I know if it is correct?
I looked at Siemens website and this forum but did not find anything. Can someone direct me to a website of someone my know the answer.
I looked at Siemens website and this forum but did not find anything. Can someone direct me to a website of someone my know the answer.
#2
Unless I'm missing something..."QT" is a Square D breaker, and wont fit in a Siemens panel...Period.
I'm assuming these are TANDEM type breakers?
Look on the label for ... "CTL CLASS"
That will determine whether or not you may use tandems.
The actual part # of the breaker should also be listed somewhere on the panel label, Indicating acceptable usage.
I'm assuming these are TANDEM type breakers?
Look on the label for ... "CTL CLASS"
That will determine whether or not you may use tandems.
The actual part # of the breaker should also be listed somewhere on the panel label, Indicating acceptable usage.
#4
www.sea.siemens.com/resident/<wbr>docs/UltimateLoad_Centers.pdf
You are Correct, QT is an accepted substitute for siemens. my apologies.
However, according to the link provided, Your panel is a 20 space /20 circuit type panel, which would be a CTL class panel.
No , you may not use tandems.
You are Correct, QT is an accepted substitute for siemens. my apologies.
However, according to the link provided, Your panel is a 20 space /20 circuit type panel, which would be a CTL class panel.
No , you may not use tandems.
#5
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Thanks so much. I reviewed this spreadsheet and determined that my panel is only rated for 20 circuits.
This is funny. I am an automotive engineer. We purposely design parts to fit where they belong and NOT fit where they should not go. So in this case, my panel should have been designed so that a tandem breaker CANNOT fit into my panel, no matter what. This is called "poke-yoke" It is a japanese word meaning "fool proof" or "mistake proof". As you can imagine if someone installed the wrong brake line, there would be devistating results. Remember the famous American Mid-sized car that had "thermal events" where there was a claim the wiring was installed incorrectly. Some people died and this all was settled out of court.
It is crazy because I would bet that there are many 20 circuit panels that have tandems just because they FIT and guys(gals) need extra circuits. This is much easier then adding a sub-panel.
This is funny. I am an automotive engineer. We purposely design parts to fit where they belong and NOT fit where they should not go. So in this case, my panel should have been designed so that a tandem breaker CANNOT fit into my panel, no matter what. This is called "poke-yoke" It is a japanese word meaning "fool proof" or "mistake proof". As you can imagine if someone installed the wrong brake line, there would be devistating results. Remember the famous American Mid-sized car that had "thermal events" where there was a claim the wiring was installed incorrectly. Some people died and this all was settled out of court.
It is crazy because I would bet that there are many 20 circuit panels that have tandems just because they FIT and guys(gals) need extra circuits. This is much easier then adding a sub-panel.
#6
Since I posted last, I have done soma looking around..
I'm a Square D guy, So siemens can be foreign to me at times.
Yes you are only rated for 20 ckts. yes , You have a CTL class panel.
But, QT is a designation for a Dual pole Breaker , not a Tandem.
What exactly is it that you have? DP's can by all means be used in your panel.......
Once again , Siemens is a bit foreign to me...so I suggest you do some further research, And I apologize for the confusion.....
Uncle D
You mean you have never "DRilled " it to fit??
I'm a Square D guy, So siemens can be foreign to me at times.
Yes you are only rated for 20 ckts. yes , You have a CTL class panel.
But, QT is a designation for a Dual pole Breaker , not a Tandem.
What exactly is it that you have? DP's can by all means be used in your panel.......
Once again , Siemens is a bit foreign to me...so I suggest you do some further research, And I apologize for the confusion.....
Uncle D
This is funny. I am an automotive engineer. We purposely design parts to fit where they belong and NOT fit where they should not go.

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I did some checking as well. The Siemens brand of breaker labeled QT is a tandem. While it will fit in my panel, my panel is only rated for 20 1" breakers. Adding tandem will not be good. So I have decided to add a sub-panel with a generator interlock kit to boot.
#9
Remember the famous American Mid-sized car that had "thermal events" where there was a claim the wiring was installed incorrectly.
