more than 42 breakers in a panel with AFCI

[[email protected]]

It looks like we will be able to have more than 42 breakers in a panel
come 2008, depending on local adoption. NEC 408.35 is going away if
things proceed as they seem. That would be a good thing with panels
being stuff full of AFCI breakers. Now they can be spaced apart in
larger panels (though you might not want to space them at every other
position unless you at least put them at the other positions on the
other side).

So how big will braker panels get? I see they have them as large as
84 slots in Canada, so I presume we could see those showing up here
around 2008.

 

[Bud--]

It looks like we will be able to have more than 42 breakers in a panel
come 2008, depending on local adoption. NEC 408.35 is going away if
things proceed as they seem. That would be a good thing with panels
being stuff full of AFCI breakers. Now they can be spaced apart in
larger panels (though you might not want to space them at every other
position unless you at least put them at the other positions on the
other side).

So how big will braker panels get? I see they have them as large as
84 slots in Canada, so I presume we could see those showing up here
around 2008.

Don't get too excited. As noted in the discussion, UL limitations still
exist. I believe UL limits 100A panels to 20 poles (at least single
phase), 40 in a 200A panel. These are class CTL (ciruit limiting).

bud--

 

[[email protected]]

| [email protected] wrote:
|> It looks like we will be able to have more than 42 breakers in a panel
|> come 2008, depending on local adoption. NEC 408.35 is going away if
|> things proceed as they seem. That would be a good thing with panels
|> being stuff full of AFCI breakers. Now they can be spaced apart in
|> larger panels (though you might not want to space them at every other
|> position unless you at least put them at the other positions on the
|> other side).
|>
|> So how big will braker panels get? I see they have them as large as
|> 84 slots in Canada, so I presume we could see those showing up here
|> around 2008.
|>
| Don't get too excited. As noted in the discussion, UL limitations still
| exist. I believe UL limits 100A panels to 20 poles (at least single
| phase), 40 in a 200A panel. These are class CTL (ciruit limiting).

UL rules are like CSA rules, and CSA allows 200 amp panels up to at least
84 circuits. They are larger panels; this isn't being achieved with a
lot of tandems. I'd bet the UL rules are based on the box size, and with
the right space,more slots would be OK. What we probably have to wait
for is the formalized testing of the new larger boxes.

Alternatively, manufacturers _may_ make boxes that are intentially spaced
out larger, with gaps in the otherwise solid stack of breakers, to give
heat dissipation room to the AFCI breakers. That's the way I would put
them in a panel, anyway: get an 84 slot panel and put them in like:

AFCI-*-|-AFCI
AFCI-|-*-AFCI
-*-|-
AFCI-|-*-AFCI
AFCI-*-|-AFCI
-|-*-
AFCI-*-|-AFCI
AFCI-|-*-AFCI
-*-|-
AFCI-|-*-AFCI
AFCI-*-|-AFCI
-|-*-
AFCI-*-|-AFCI
AFCI-|-*-AFCI
-*-|-
AFCI-|-*-AFCI
AFCI-*-|-AFCI
-|-*-
AFCI-*-|-AFCI
AFCI-|-*-AFCI
-*-|-
AFCI-|-*-AFCI
AFCI-*-|-AFCI
-|-*-
AFCI-*-|-AFCI
AFCI-|-*-AFCI
-*-|-
AFCI-|-*-AFCI
AFCI-*-|-AFCI
-|-*-
AFCI-*-|-AFCI
AFCI-|-*-AFCI
-*-|-
AFCI-|-*-AFCI
AFCI-*-|-AFCI
-|-*-
AFCI-*-|-AFCI
AFCI-|-*-AFCI
-*-|-
AFCI-|-*-AFCI
AFCI-*-|-AFCI
-|-*-

 

[[email protected]]

I'd bet the UL rules are based on the box size, and with
the right space,more slots would be OK. What we probably have to wait
for is the formalized testing of the new larger boxes.

U/L will do whatever the manufacurer's tell them to do.
They manufacturer can submit a 200 slot panel and U/L will test it and
if it doesn't burst into flames they will list it.
Whether an AHJ actually accepts it is up to the AHJ as guided by NFPA,
NEMA or their local union rep.

 

[Bud--]

U/L will do whatever the manufacurer's tell them to do.
They manufacturer can submit a 200 slot panel and U/L will test it and
if it doesn't burst into flames they will list it.
Whether an AHJ actually accepts it is up to the AHJ as guided by NFPA,
NEMA or their local union rep.

The NEC currently allows single phase residential panels with 42 poles.
Does anyone make a 100A panel that allows installation of more than 20
poles? Or more than 40 poles in a 200A panel? Far as I know the UL
standard does not permit it.

bud--

 

[[email protected]]

52:49 GMT, [email protected] wrote:
|
|> I'd bet the UL rules are based on the box size, and with
|>the right space,more slots would be OK. What we probably have to wait
|>for is the formalized testing of the new larger boxes.
| U/L will do whatever the manufacurer's tell them to do.
| They manufacturer can submit a 200 slot panel and U/L will test it and
| if it doesn't burst into flames they will list it.
| Whether an AHJ actually accepts it is up to the AHJ as guided by NFPA,
| NEMA or their local union rep.

How often do they burst into flames? I'm just curious how fun of a job
it is at the UL testing facilities.

In Canada, Square-D already sells (under the Schneider name), NF series
panels with 54 and 66 spaces, and NQOD series panels with 54, 72, and 84
spaces. The QO series has a 60 space panel, as well as a 40 space panel
that is rated for 64 poles (presumably using 24 tandems and 16 full size
breakers). Maybe they will take these same designs and submit them to
UL for testing to get listed in the US (if not already) and start selling
them in areas where NEC 2008 gets adopted. I looked for larger Canadian
panels from Eaton Cutler-Hammer, but could not find any.

 

[[email protected]]

| [email protected] wrote:
|> On 8 Oct 2006 17:52:49 GMT, [email protected] wrote:
|>
|>
|>> I'd bet the UL rules are based on the box size, and with
|>>the right space,more slots would be OK. What we probably have to wait
|>>for is the formalized testing of the new larger boxes.
|>
|> U/L will do whatever the manufacurer's tell them to do.
|> They manufacturer can submit a 200 slot panel and U/L will test it and
|> if it doesn't burst into flames they will list it.
|> Whether an AHJ actually accepts it is up to the AHJ as guided by NFPA,
|> NEMA or their local union rep.
|
| The NEC currently allows single phase residential panels with 42 poles.
| Does anyone make a 100A panel that allows installation of more than 20
| poles? Or more than 40 poles in a 200A panel? Far as I know the UL
| standard does not permit it.

Eaton Cutler-Hammer has listed in their catalog, CH series panels that
have up to 30 spaces for 100 or 125 amp, 32 spaces for 150 amp, 42 spaces
for 200, 225, 300, or 400 amp. These are main breaker panels. Main lug
panels only go up to 24 spaces for 125 amp, 32 spaces for 150 amp, 16
spaces for 200 amp (probably just an odd bus here), and 42 spaces for
225 amp. I suspect some of the lower amperage MCB panels really have
larger busses but with mountings for smaller main breakers.

Square-D has similar, but I did notice a 100 amp MCB panel up to 32 spaces
in the QO series.

I did not look at BR or HOM series, or other brands like GE or Siemens.

Do you have a copy of the UL standard that limits 200 amp panels to no more
than 40 poles?

 

[Tom The Great]

The NEC currently allows single phase residential panels with 42 poles.
Does anyone make a 100A panel that allows installation of more than 20
poles? Or more than 40 poles in a 200A panel? Far as I know the UL
standard does not permit it.

bud--

I have a 40 branch circuit 200a panel, but then the main disconnect
counts as two. So 42 here.

later,

tom @ www.FreelancingProjects.com

 

[[email protected]]

| On Mon, 09 Oct 2006 02:24:05 -0500, Bud-- <[email protected]>
| wrote:
|
|>[email protected] wrote:
|>> On 8 Oct 2006 17:52:49 GMT, [email protected] wrote:
|>>
|>>
|>>> I'd bet the UL rules are based on the box size, and with
|>>>the right space,more slots would be OK. What we probably have to wait
|>>>for is the formalized testing of the new larger boxes.
|>>
|>> U/L will do whatever the manufacurer's tell them to do.
|>> They manufacturer can submit a 200 slot panel and U/L will test it and
|>> if it doesn't burst into flames they will list it.
|>> Whether an AHJ actually accepts it is up to the AHJ as guided by NFPA,
|>> NEMA or their local union rep.
|>
|>The NEC currently allows single phase residential panels with 42 poles.
|>Does anyone make a 100A panel that allows installation of more than 20
|>poles? Or more than 40 poles in a 200A panel? Far as I know the UL
|>standard does not permit it.
|>
|>bud--
|
|
| I have a 40 branch circuit 200a panel, but then the main disconnect
| counts as two. So 42 here.

The rule that limits the panel to 42 poles does not count the main.

 

[Bud--]

| [email protected] wrote:
|> On 8 Oct 2006 17:52:49 GMT, [email protected] wrote:
|>
|>
|>> I'd bet the UL rules are based on the box size, and with
|>>the right space,more slots would be OK. What we probably have to wait
|>>for is the formalized testing of the new larger boxes.
|>
|> U/L will do whatever the manufacurer's tell them to do.
|> They manufacturer can submit a 200 slot panel and U/L will test it and
|> if it doesn't burst into flames they will list it.
|> Whether an AHJ actually accepts it is up to the AHJ as guided by NFPA,
|> NEMA or their local union rep.
|
| The NEC currently allows single phase residential panels with 42 poles.
| Does anyone make a 100A panel that allows installation of more than 20
| poles? Or more than 40 poles in a 200A panel? Far as I know the UL
| standard does not permit it.

Eaton Cutler-Hammer has listed in their catalog, CH series panels that
have up to 30 spaces for 100 or 125 amp, 32 spaces for 150 amp, 42 spaces
for 200, 225, 300, or 400 amp. These are main breaker panels. Main lug
panels only go up to 24 spaces for 125 amp, 32 spaces for 150 amp, 16
spaces for 200 amp (probably just an odd bus here), and 42 spaces for
225 amp. I suspect some of the lower amperage MCB panels really have
larger busses but with mountings for smaller main breakers.

Yup, looks like CH has panels over my 30/40 limit.

Square-D has similar, but I did notice a 100 amp MCB panel up to 32 spaces
in the QO series.

I had thought my old SqD catalog didn't have poles above a 20/40 limit,
but there were somer even in that old catalog that were over. I was
wrong about the UL limit.

I did not look at BR or HOM series, or other brands like GE or Siemens.

Do you have a copy of the UL standard that limits 200 amp panels to no more
than 40 poles?

Nope. Sure would be nice if the UL standards, or a good summary, were
available online.

--------------
The commentary in the ROP says the 42 pole limit also appears in the UL
panelboard standard, so you will have to wait for bigger panels until
the UL standard is changed.

bud--

 

[[email protected]]

| Nope. Sure would be nice if the UL standards, or a good summary, were
| available online.

Best they have is an index. It would be nice to know what they test
for so the public understands the value of the mark. But alas, most
of the public is essentially a zombie in this regard.