80 circuit panel?

[kbsparky]

It is my understanding that the 42 circuit limitation for most panelboards and load centers will become a thing of the past once the 2008 edition of the NEC is adopted. The argument was that rule was implemented 80 some years ago when the use of rubber-covered conductors was prevalent, and installing more than 42 circuits in a single panel could overheat to the point of starting a fire.

Conductor insulation, wiring methods and overcurrent equipment have improved significantly in the time since then, so it would be logical that such an outdated requirement would be rescinded.

It has been pointed out in another thread here that some manufacturers make panels for use in other countries that do not have this limitation. Case in point from a recent listing for a 200 Amp panel on eBay from Canada:

Here we can plainly see that this 40 space panel is capable of handling up to 80 circuits.

Since the trend is to standardize the Codes from the US and Canada (meaning uL and CSA among others), this would seem to be what is in store for us?

 

[bphgravity]

Here is a post I made regarding the topic on another Forum:

The 42-space rule is truly an obsolete code that really doesn't need to exist any longer. The original rule was established in 1933 after several fires (the most famous being the 1928 fire at the Waldorf Astoria in NYC).

At the time, Rubber insulated conductors were the norm and would easily overheats when one too many were installed in panelboard enclosures. At the time, UL did not provide the current requirements for "space" which is now provide in excess when in compliance with UL 67. With the use of 90?C insulated conductors and loading limited to 75?C in most cases, this problem doesn't exist anymore.

Also, Canada does not have this restriction and there does not appear to be any reported problems with panelboards containing more than 42 overcurrent devices.

 

[LawnGuyLandSparky]

Another plus would be, an 80 ckt. panel filled with the new AFCI requirements might eliminate the need for auxiliary garage heating!

 

[bphgravity]

Funny you mention that!

Check out the entire topic that was posted from the other Forum. I think the same questions was posted here...


http://www.iccsafe.org/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=11;t=001240;p=1#000031

 

[cowboyjwc]

Remember that the 42 circuit limit is only for "Lighting and Appliance Branch-Circuit Panelboards". One having more than 10% of its overcurrent devices protecting lighting and appliance breanch circuits.

 

[bphgravity]

I believe the 2008 will also drop the panelboard designations...

 

[brantmacga]

this panel is probably almost exactly like what you can buy here in the US. you'd only get 80 circuits using tandem breakers. if you buy a 6 space panel, it says its capapble of 12 circuits, and so on.

 

[LAYMAN JOE]

Its a 40 space panel.Add breakers rated for two connections would make it an 80 circuit panel. 80 circuits but still less than 42 breakers.

 

[iwire]

I am not following you Joe.

Right now we are limited to 42 overcurrent devices.

One 'twin breaker' is two overcurrent devices

 

[yanici]

I for one am waiting in gleeful anticipation for these 40/80 circuit panels. When the tandem afci's are introduced, we'll all be able to cook our hot dogs, for the game, on them. Just think of them as a kitchen small appliance.:grin: :grin:

 

[LAYMAN JOE]

I am not following you Joe.

Right now we are limited to 42 overcurrent devices.

One 'twin breaker' is two overcurrent devices

The manufacturer of that panel left "40 spaces". Yet the sticker states "80 circuits". I dont think they meant the panel is rated for 80 overcurrent devices (that would be a violation of NEC). I think square D (in this case) considers two wires terminating onto one single pole breaker as two circuits. Two circuits taking up one space. That way they can say our panel can have 80 circuits when we know that it would only be 40 circuits. (ooh, Ill get the one that can have more circuits). I think its simply a marketing ploy... Sorry for the confusion.

 

[don_resqcapt19]

Joe,
That panel is for Canada and they do not have the 40 overcurrent protective device limit like the NEC now has.
Don

 

[LAYMAN JOE]

Don,

Its the same panel you get in the US. I have one in my basement.

 

[LAYMAN JOE]

BTW Don, I like your AVATAR. Have you seen the video of the 500kv switch opening?

500 kv switch opening.

Oil filled transformer exploding
and to think my co-worker took an oil sample from a 35 kv xfrmr and came back a year later to do the same maintenance to find he left the oil plug off. This was an outside transformer.

 

[brantmacga]

The manufacturer of that panel left "40 spaces". Yet the sticker states "80 circuits". I dont think they meant the panel is rated for 80 overcurrent devices (that would be a violation of NEC). I think square D (in this case) considers two wires terminating onto one single pole breaker as two circuits. Two circuits taking up one space. That way they can say our panel can have 80 circuits when we know that it would only be 40 circuits. (ooh, Ill get the one that can have more circuits). I think its simply a marketing ploy... Sorry for the confusion.

incorrect. two wires on one breaker is still one circuit. a tandem breaker is two ocpd's. 40 tandems = 80 circuits. 40 sp's = 40 circuits, no matter how many wires.

 

[LAYMAN JOE]

incorrect. two wires on one breaker is still one circuit. a tandem breaker is two ocpd's. 40 tandems = 80 circuits. 40 sp's = 40 circuits, no matter how many wires.

I agree! Please dont misunderstand me. 40 tandem breakers is 80 circuits. 40 sp breakers with two wires on it is still only 40 circuits, not 80.

I thought I was clear in stating my opinion that its a play on words by square D (a marketing ploy). They give you 40 spaces, say it can have 80 circuits, and sell it in the US where it would be a violation to have more than 42 circuits.
Why would they advertise a product that would violate NEC? It doesn't make sense. It must be a marketing ploy for the do it yourself home owner. As I said:

That way they can say our panel can have 80 circuits when we know that it would only be 40 circuits.

Im not the best at clearly communicating through writing, sorry.

 

[iwire]

Joe the 42 limit is being removed and never existed in Canada.

Under the 2008 NEC we will be able to install 40 tandems in a 40 space panel that will result in 80 overcurrent devices or 80 circuits in one panel

 

[infinity]

Joe the 42 limit is being removed and never existed in Canada.

Under the 2008 NEC we will be able to install 40 tandems in a 40 space panel that will result in 80 overcurrent devices or 80 circuits in one panel

Does everyone agree that this is a good idea?

 

[Dennis Alwon]

Does everyone agree that this is a good idea?

I do--- 80 tandem arch faults- someone else said they wouldn't have to heat their basement. I might try grilling hot ogs on it.

 

[brian john]

I'd prefer an 80 space panel no tandems, only takes two electricians and a helper to mount it.