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#48723 - 02/18/05 06:44 PM How many breakers?
Local3Jr Offline
Member
Registered: 01/06/05
Posts: 10
Loc: Wantagh,NY
How do you figure out how many breakers you can fit on a 100,150,200 amp panel?
Thanks for any info.......
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#48724 - 02/18/05 06:46 PM Re: How many breakers?
SolarPowered Offline
Member
Registered: 07/05/04
Posts: 615
Loc: Palo Alto, CA, USA
Isn't it printed on the labels of your panels? It should be.
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#48725 - 02/18/05 09:02 PM Re: How many breakers?
Local3Jr Offline
Member
Registered: 01/06/05
Posts: 10
Loc: Wantagh,NY
let me reword it,if you have a 100 amp panel, how do you know how many 15 or 20 amp breakers you can use?
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#48726 - 02/18/05 09:07 PM Re: How many breakers?
e57 Offline
Member
Registered: 05/27/03
Posts: 2837
Loc: S.F.,CA USA
12/24 + 12 full size, or 24 1/2 size. Same for 20/30, 8/16, 30/36, 30/42

If not marked in that way it would be marked with how many spaces or (30/30 all full size), as would be any panel that half size aren't made for like bolt ons. i.e. a 24, 30 or a 42.

I heard that in Canada you can get 84?
_________________________
Mark Heller
"Well - I oughta....." -Jackie Gleason
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#48727 - 02/18/05 09:11 PM Re: How many breakers?
e57 Offline
Member
Registered: 05/27/03
Posts: 2837
Loc: S.F.,CA USA
Oh how many can you fit of 15 or 20's. You can fill it up! Even throw some 50's or larger and feed another panel from it.

So long as the load calc is OK, maybe that is what you're really looking for.....
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Mark Heller
"Well - I oughta....." -Jackie Gleason
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#48728 - 02/18/05 11:01 PM Re: How many breakers?
bucketman Offline
Member
Registered: 10/31/04
Posts: 71
Loc: vancouver WA, USA.
NO MORE THAN 42 OTHER THAN THE MAINS
408.15
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#48729 - 02/19/05 02:08 AM Re: How many breakers?
iwire Offline
Moderator
Registered: 01/05/03
Posts: 4343
Loc: North Attleboro, MA USA
Local3Jr never more than 42 overcurrent devices in one enclosure (excluding the main)

But you can have as many breakers as you want connected to any service.

100 amp service go ahead and install ten 42 circuit sub panels and fill them up with breakers.

The only thing that matters is that the calculated load is less than the service size.

Say you are planing to wire a house in the 'normal' way with the code minimum circuits and the calculations show a 100 amp service will do the job.

Now the future homeowner says they want every receptacle, switch and appliance on it's own circuit.

To do this you will need a few sub panels and lots of breakers but the calculated load remains the same. The 100 amp service will still be fine.

Bob
_________________________
Bob Badger
Construction & Maintenance Electrician
Massachusetts
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#48730 - 02/19/05 02:50 AM Re: How many breakers?
shortcircuit Offline
Member
Registered: 06/27/04
Posts: 608
Loc: massachusetts
e57...I recently read the label on a 200 amp Cutler Hammer loadcenter that did specify 84 overcurrent devices in Canada.

But why would the same panel used in Canada be able to handle 84 breakers with out failure?

shortcircuit
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#48731 - 02/19/05 03:18 AM Re: How many breakers?
shortcircuit Offline
Member
Registered: 06/27/04
Posts: 608
Loc: massachusetts
note...408.15 has disappeared in the 2005 NEC...

wait a minute...its at 408.35 now

shortcircuit
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#48732 - 02/19/05 06:29 AM Re: How many breakers?
Local3Jr Offline
Member
Registered: 01/06/05
Posts: 10
Loc: Wantagh,NY
Sorry for the confusion guys,lets say you have a 100 amp 3 wire panel(a phase,b phase and a neutral. Each leg is 100 amp right? You wouldn't be able to load it up with 42 20 amp breakers right? Maybe I am looking for some kind of calculation. Thanks again
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