On Fri, 7 Apr 2006 16:46:04 -0400, "Eric Tonks"
etonks@sunstormADD-DOT-COM wrote:

Only if you are planning to use up to 300 or 400 amps, otherwise he is full
of BS, sounds like a sales pitch to get you to pay a premium for the extra
amps. More important is to get a panel with as large a capacity of circuit
breakers as you can, which may take more than one panel to do the job, so
that there are a lot of lightly loaded circuits instead of loading each
circuit to the max.

I agree with you.

But you remind me of a long time question I've had.

When I lived in a 1930 apartment building, the fuse box in my apt. had
2 slo-blo 15 amp fuses, and in the basement the fuse that served my
apt. was 1 slo-blo 20 amp fuse.

I was told this was bad, because 2 x 15 = 30 which was more than 20.
I was told the sum of the fuses downstream should never be more than
the upstream fuse. Any truth to this????**

I sort of figured first, that the landlord would not rewire the whole
building and I needed my 30 amps, so I should keep my mouth shut.
second, the building had been working this way since
1930 and there were no electrical fires, and that's still true today,
75 years after construction.
and third, the 20 amp fuse in the basement would protect
the 12 gauge wire from the basement to the 5th floor. That was its
job. But there were sometimes I would use 14 amps through one fuse
and 5 through the other, and that would be under 15, and under 20
total so what's wrong with that. Anything higher would blow one fuse
or the other.

**If there is any truth to the idea that two 15 amp fuses can't feed a
20 amp fuse, why is it all right for the sum of all my circuit
breakers to be greater than the main serving my house. I have cb's
totally 200 or more amps now, and room in the box for in the box for
120 amps more. Maybe more. I'll never use anywhere near all of it
at once, but if this is ok, why was my apartment setup not ok??


BTW, slo-blo is only 5 or 10 seconds, right? It's more than 1/2
second like non-slo-blo, but no where near 30 seconds, is all of this
so?


This will give you more "head room" in each circuit so
the ones that end up with a load are not overloaded. Also to provide a
separate circuit for each large load or critical load such as a separate
line for a freezer, etc.

"Sanj" wrote in message news:u_zZf.64$ee6.4@trndny01...
My homebuilder says upgrading my electric service to 300 or even 400 Amps
will result in more "efficient" use of electricity by my appliances. Can
one of you experts out there please explain how this is so?