New one on me

I guess we are saying the same thing I am just pointing out “main” in this case is not “service disconnect” and that might confuse people who think “I pulled the MAIN, why didn’t everything go off”. The other thing is they are using the size of the “main” to determine the service size.

I guess what’s most important right now, is what size are the cartridges inside the left pull-out?

Wrong thread deleted and relocated message

They can be no larger than 60A, same as the right side.

Two “mains”, with a maximum of 60A each.
100A service.

I don’t know why this is so confusing. Most of you are clear on what a split-buss breaker panel is. This is no different.

I don’t see split buss panels in my area.

Tell me something, what is the purpose of using a split buss panel (2 60 amp pulls) verses a simple 100 amp panel?

I’m very suprised you don’t see them in Ma. We see them ALL the time here in eastern NY.

I’m not sure what the answer is though.
Possibly that one big main was not required, and if one of the several smaller mains tripped it would not take out the whole house? I’m really not sure of the original intent of that design.

The fuse panels were designed that way and used for a LONG time, and breaker panels were very popular in the 50’s & 60’s.

Hmmm, I can’t recall ever seeing them here. If I did inspect one, I wasn’t aware of it being a spilt buss.

I think it was simply the cost of 100a fuses. You could put in a pair of 60s to run the 120v and then use other pullouts for the range and any other 240v loads. My next door neighbor has a 4 pullout split bus panel, installed in the 60s. One P/U controls 8 (or 10?) plug fuses, one goes to the water heater, one for the range and one for the wall heaters. I really try to stay away from this thing. I did take out all the 30a fuses and replace them with 20s but since they have fuse stat adapters and I don’t have the tool I couldn’t get them to the 15s that belong in there.
I have told this lady a bunch of times she needs a panel upgrade and I won’t work on it.

Here’s a diagram of this equipment along with an explanation:

http://www.joetedesco.org//oldbox.JPG

Good picture Joe

So that is not a split bus panel? My appologies.

In all my years I also always thought that was a split buss panel where both pull-out were “mains”.

That’s certainly what I’d call it.

So, if you pull the “Main” fuse block, does the range fuse block feed go dead?
I always thought no.

I’ve never actually tried this.

That’s certainly what it is. The service splits into two directions (under two set of fuses) thus a “split” bus panel

Nope, the only thing that goes dead is the Edison or S-based fuseholders below and the subfeed lugs.

I THOUGHT SO. That diagram is “misleading” then.

I have to flip-flop then. I’m going back to 100A “split-buss”.

That diagram certainly does show the range pullout powered from the load side of the ‘main’ fuses, but I’ve never seen one made like that. There might be some out there that way, but I can’t recall running across one.

I know that I have looked at a few of those schematics for panels when I have inspected them, and that is the way I remember them being wired. I would say the best advice is to look for a label as to the panel rating and look for a diagram/schematic.

It would be nice to be able to pull the fuses out to check the amperage, but the only time I might do that is if the house were vacant.

Marc, Joe, anybody else,
Do you have 1 or 2 books you would recommend that show the different types of panels. Old and new With the correct way of wiring them.
Thanks
Mark