Proper spot for tandem breakers
#1
12-31-14, 11:14 AM
Proper spot for tandem breakers
According to this label, would it be the locations where the "----" are? Looks like it says it's OK for two .5" breakers.
Thanks.
Thanks.
#5
12-31-14, 07:44 PM
Member
According to this label, would it be the locations where the "----" are?
#6
12-31-14, 11:50 PM
Crouse-Hinds made regular tandems before the half-hook stab clip version. Same part number as today's Murray (MP1515 and MP2020).
Good point about the other vendors. Lots of Bryant BR's are seen in these old panels.
Good point about the other vendors. Lots of Bryant BR's are seen in these old panels.
#9
01-11-15, 05:00 PM
Just went to HD and bought a couple tandem breakers, although I bought the 'U' suffix instead of the 'N', and I need the 'N'. As you know, the 'U' has an extra little piece of plastic / metal on it to keep it from being installed (on my panel). I kind of want modify it myself (don't worry I won't). I can't see why the 'N' ones would be double the cost. The ones that are in there already 'N'.
#10
01-11-15, 05:53 PM
Forum Topic Moderator
Some tandems are for replacement use only and do not have the rejection foot. This should not be used in CTL panels.
#11
01-11-15, 06:30 PM
Nevermind, I'm an idiot. I judged the book by its cover. I removed one of the tandems that was in there and saw that it was the unrestricted version, so I assumed that's what it needed... not so. The tandem spots on the main strip (not sure what the real name for this is) are notched out to accept the U version of the breakers. So I'm all set.
#12
01-11-15, 08:42 PM
Forum Topic Moderator
The slot is the rejection feature to limit the number and placement of tandems. You have a CTL class panel.
CTL circuit tandem limiting.
CTL circuit tandem limiting.
#13
01-12-15, 08:13 AM
Member
I can't see why the 'N' ones would be double the cost.
Non-CTL replacement only
Circuitboards and panelboards built prior to 1965 do not have circuit total limiting devices or features built-in. Even so, pre-CTL circuit breakers "for replacement use only"[2] are still sold in local hardware stores. As a result, numerous unsafe situations have resulted where panels were dangerously overloaded because these non-CTL breakers continue to be used.[citation needed] With overuse of non-CTL breakers, current is being placed on the panel's bus-bars in excess of the designed capacity of that panel.
The 2008 code did away with the previous 42 circuit limitation on panelboards.[3] One can now order panelboards with as many as 84 circuit places, and a corresponding ampacity rating. If a panelboard with a sufficient number of breaker positions is installed in the first place, the need for non-CTL breakers should be eliminated.
Circuitboards and panelboards built prior to 1965 do not have circuit total limiting devices or features built-in. Even so, pre-CTL circuit breakers "for replacement use only"[2] are still sold in local hardware stores. As a result, numerous unsafe situations have resulted where panels were dangerously overloaded because these non-CTL breakers continue to be used.[citation needed] With overuse of non-CTL breakers, current is being placed on the panel's bus-bars in excess of the designed capacity of that panel.
The 2008 code did away with the previous 42 circuit limitation on panelboards.[3] One can now order panelboards with as many as 84 circuit places, and a corresponding ampacity rating. If a panelboard with a sufficient number of breaker positions is installed in the first place, the need for non-CTL breakers should be eliminated.
