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Re: Arc Fault Breaker?

Thanks for the info. Good point on a firm quote.

Re: Arc Fault Breaker?
kentvw wrote:

Split bus panels used to be pretty common but they have not been approved for use by the NEC since the 80's(?)

I spent an entire summer replacing them on homes.

Thanks for the info....:)

Re: Arc Fault Breaker?
DwarfWytch wrote:

ITE, Fed pacific, Zinsco, a canadian square-D subsidiary also named Federal, and others made them.

The greater than 10% for light/receptical/small appliance circuits (those single pole 15 & 20 amp circuits) rule of 2 motions rule kicked in in the early 80s which overrode the rule of 5/6.

So, grandfathered in if existing, but required to be changed if modifying, and all the sp 15/20 circuits have to be on the one breaker, unless you have a master before the panel.

As I said earlier, never recall having seen one that was originally listed for more than 150 amps (most I've seen were 100, 125 or 150 amps). Obviously one could physically load double pole breakers that equaled more than that; which you often find these are overloaded beyond their original listing.

The cost was the issue, which was why they were thought to be a good idea for residential, you could buy a 60 amp plus fill the remaining double pole breaker spots and all the single pole breakers for less than the cost of a single 100 amp double pole main breaker, and with the split bus, still met the rule of 5/6 motions.

Most of these oldie moldies also have far to little gutter room in the panels, especially when some later HO has "upgraded" with a higher amp CB and wire.

Thanks for the info. Learned a few things....:)

Re: Arc Fault Breaker?

Keep in mind that the NEC still makes an exception allowing split bus panels on existing individual residential occupancies.

Re: Arc Fault Breaker?

Interesting though, the 2008 code completly revises article 408.36 and does away with articles 408.34 and 408.35. There is no longer a reference to lighting and appliance panelboards and the limitations according to percentages of breakers or circuits is gone. If you have a OCPD ahead of the panel the 42 circuit limitation is gone as well.


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