Fuse Panel Service Size

Inspected 45 year old home with fuse main distribution panel. 5 pull out fuses with main pull out fuse 40 amp supplying 9 branch circuits. Additional pull out fuses were 60 amp, 30 amp, 20 amp and 1 pull out with no fuses and no distribution wires. Is the service size 40 amps or do add up 40 + 60 +30 + 40= 150 Amps? This is first for me. The homes that I have inspected had 1 pullout with either 100 amp or 150 amp fuses.

only count the main fuse which you said was 40

The “main” is feeding the lower bus, it appears. The upper bus has no “main”. Thus the service size must be determined based on the feeder size or the panel rating. My guess would be 100 amps, but I would say in the report that it could not be determined. Looks like lots of double taps, so let the sparky make the call.

There is 1 main disconnect. The other fuse blocks probably supplying other 240 volt circuits for appliances , range , dryer , a/c even or even another distribution panel. All the blocks must be removed to disconnect everything completely. You say its 45 yrs old. 1968 or so. Prob 100 amp. 150 started mostly in the 1970 s. But remember the Weakest link determines the true size.

Thanks. Yes the other blocks were supplying dryer, AC and other undetermined appliances/fixtures and removing all fuse blocks disconnects all power. Also, I am noting in my report about double taps, openings in the panel (missing screw in fuses) and additional items, however I was stumped on service size. I understand that the weakest is service but the smallest pullout fuse was a 20 amp = the weakest? Is 20 Amps the service size?

Are you sure there is not a disconnect up stream from this box .

Regardless I would say it is obsolete and recommend an immediate upgrade to a modern service .CYA

What about this comment?
The main electrical distribution panel employs fuses. It may be in your best interest to upgrade the main panel to current residential standards using breakers. I recommend consulting with a qualified electrician to evaluate and discuss upgrade options for this system.

These two statements are contradictory to each other, and only the latter is correct.

Removal of all six fuse blocks is required to disconnect all ungrounded conductors. This is the definition of the “service disconnect.”

Bad choice of wording on my part. Meant the Main as in turn off for the 120 volt circuits. Sorry for confusion

This is a split buss panel. Probably 100 or 125 depending on service entrance conductors.

Regardless of what the label states the 40 amp fuse is not the service disconnect. There are 5 service disconnects. The service size will be determined by the size of the service entrance conductors.

5 or only 1?

Now many are in photo #4?

I only see one service disconnect that consists of 5 disconnect cartridges. I thought that was the proper way to describe it?

Which one would be the service disconnect? I see 5 pull out type disconnects and no single main. The one labeled MAIN is probably feeding the Edison base fuses on the bottom.

All of them would be the service disconnect.

I just thought the way to desribe is that each service has one disconnecting means which could consist of 6 breakers or pull outs.

Obviously there is no “main” in the photo.

At this point it’s a terminology thing I’m trying to clarify.

Typically a service would have one main disconnect or up to 6 individual disconnects grouped together in one location (there are some exceptions that aren’t germane to this installation).

Since there is no singular main disconnect, this service has 5 service disconnects.

Juan - you could say “the disconnect consists of 5 pull-out cartridges,” or “5 fuse blocks.”