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Joined: Oct 2002
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I have several of the long type square d breakers and would like to know a number for them. I'm trying to make a list of the "special" used breakers I have in stock, and so far can't find them online because I don't know how to punch them in. They are the type that just plugs in a residential panel that takes up both sides. Thanks... By the way they are 3 phase breakers...

Last edited by sparkync; 05/09/13 01:43 PM.
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Sparkync:
Sounds like an older style QO IMHO.
It takes up 6 spaces for 3 phase, & 4 spaces for single phase, from my memory.

Try the Sq D website, or if you can find an older Sq D catalog (called 'Digest' back then) they used to be in there.

Probably some version of QO-390, or QO-3100.


John
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Thanks John. I had looked on the breaker before, but your post got me checking first a Square D "Digest" catalog I had, then it "sparked" smile my mind to look on the breaker again. On the side of the breaker there was a piece of paper that was almost torn off, but I pieced it back together and came up with QI390, pulled it up on the web, got a hit for ebay; went to ebay and they got one on there for $ 12.50 frown Can't believe someone selling that cheap. I know it's out of date, but what if one burnt up in a panel, it would be worth lot more. But again if it was me needing it, I would be glad to pay $12.50 for it smile Just depends on whether you're trying to buy or sell smile Thanks again for the help....

Last edited by sparkync; 05/09/13 05:59 PM.
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Originally Posted by sparkync
On the side of the breaker there was a piece of paper that was almost torn off, but I pieced it back together and came up with QI390, pulled it up on the web, got a hit for ebay; went to ebay and they got one on there for $ 12.50 frown Can't believe someone selling that cheap. I know it's out of date, but what if one burnt up in a panel, it would be worth lot more. But again if it was me needing it, I would be glad to pay $12.50 for it smile Just depends on whether you're trying to buy or sell smile Thanks again for the help....


The Q1 breaker family was obsoleted some 30years ago.
An equivalent rated QO breaker is a 100% adequate replacement (except for the 'top feed' main breaker version - Q12100TF).

Joined: Apr 2002
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If someone needs an obsolete breaker for replacement, the cost is whatever the traffic will bear.

That said, the integrity of any used breakers can be questionable, unless they are tested and/or reconditioned. Even then, it could become a liability for the installer.

Also, most 'old' breakers may not have a compliant AIC rating.



John
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I had one of those in my MLO panel when I bought the house. (100a) The difference is it is service rated and the regular double slot breaker isn't (lower AIC rating).
It was flaky and one of the reasons that drove my service upgrade.


Greg Fretwell
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Originally Posted by gfretwell
....The difference is it is service rated and the regular double slot breaker isn't (lower AIC rating).
It was flaky and one of the reasons that drove my service upgrade.


Not true.
The only thing unique about the Q1 family was the Top-Feed Main Breaker version (Q12100TF) used in some loadcenters.

The Q1 family of breakers were not special. They were simply leftovers from the original introduction of the QO family, back in the 50's. By the 80's Square D had introduced the higher ampacity QO breakers that we know today.

If anything the newer QO breaker has higher AIC ratings, as well as series-combinations ratings. Service entrance ratings go with the panel/enclosure not the breaker.

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This was 30 years ago so I am a little fuzzy on all of the details but when I looked for a replacement breaker, the common 2 slot breaker was only 10,000 amp and the wide breaker was supposed to be 22,000 as I recall. I did not have an AFC calc from the PoCo but I was guessing it was >10,000 since I was about 60' from a 37KVA pole pig.
Truth be told I used the 10k breaker but only until I could get the service upgraded.

... or I could just be confused. I am old you know wink


Greg Fretwell
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Originally Posted by gfretwell
This was 30 years ago so I am a little fuzzy on all of the details but when I looked for a replacement breaker, the common 2 slot breaker was only 10,000 amp and the wide breaker was supposed to be 22,000 as I recall. I did not have an AFC calc from the PoCo but I was guessing it was >10,000 since I was about 60' from a 37KVA pole pig.
Truth be told I used the 10k breaker but only until I could get the service upgraded.

... or I could just be confused. I am old you know wink


You just didn't know about the QO290VH, which would provide a 22/10 series rating.

My point was that the QO breaker is an acceptable replacement for a Q1. Not doing any head banging, just trying to be helpful to the next person. I think this is the second time I have seen this topic in the past month or so, but I can't remember for sure. wink

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SparkyNC:

The Devices I believe you are referencing are the "Sub-Feed" types, which are placed on the actual Bus Kit its self; as opposed to being connected to the Bus Kit via Lug Landing Studs + Breaker Mounting Accessories.

The QO/QOB Line of "Sub-Feed" Circuit Breakers, for use on NQOD Bus Kits, use the Standard Catalog Numbering Protocol as a typical QO/QOB Device, with the letters "SL" preceding the Frame Designation.

For example, a Two Pole, 90 Amp Sub-Feed Plug-On Device would be Catalog No.: QO290SL
The Three Pole version of the 90 Amp Sub-Feed Plug-On Device would be Catalog No.: QO390SL

For the Bolt-On (QOB) versions of the Sub-Feed Devices, the Catalog Numbers will be QOBXXXXSL
Catalog Number examples using the 90 Amp Trip Rating:
QOB290SL for the Two Pole Bolt-On,
QOB390SL for the Three Pole Bolt-On.

The Plug-On Sub-Feed Breakers will have Two Sets of Clips, so the Device connects to both the Left AND Right side Bus Tabs.
The Two Pole versions will have a total of (4) Bus Clips, and the Three Pole versions will have a total of (6) Bus Clips.

The Sub-Feed Breakers look like a typical QO/QOB Device (Trip Handle, Trip Indicator, Mounting and Bus Tabs, Frame width and height, etc.), except they extend across the full width of the NQOD Bus kit.

Sub-Feed Breakers are completely different from the Designated "Main Circuit Breakers".
These are the "QOM1" and "QOM2" Series of OCPDs, which do not attach to the Bus Kit at the Branch Device spaces; instead these Devices are separately mounted at One "End" of the Bus Kit, and have Terminals which attach to the Bus Kit in lieu of Main Lugs.
The Line Side of these Devices have Lugs, which Terminate the incoming Feeders.

"Sub-Feed Breakers" and "Main Circuit Breakers" have completely different appearances and characteristics, it would be nearly impossible to mistake the two device types.

Main Circuit Breakers would be considered as "Bolt-On Only", whereas Sub-Feed Breakers may be either "Plug-On" or "Bolt-On".

Sub-Feed Breakers mount on the Bus Kit, in the Spaces designated for Branch Circuit Breakers (the Distribution Bus Section);
Main Circuit Breakers are mounted separately (remotely) from the Bus Kit, and Terminate to the Bus Kit at the "Mains Section" only.

--Scott (EE)


Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!
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