"Pete C." wrote in message
...
PrecisionMechanical wrote:

wrote in message
oups.com...
A good friend has a FPE 100 amp cabinet. Obviously the breakers are
JUNK! He lacks the $ for a new service right now. He wonders if he
could replace the 100 FBE cabinet with a 200 amp new service but
install for now a 100 amp main breaker till he has the bucks to
replace
the service completely.

Anything unsafe about this rather creative idea?


The mains breaker only protects the buss that it's being tasked with
feeding....and so it follows that it's utility as to providing
overcurrent
protection has absolutely nothing to do with the ampacity of the circuit
that it's being fed from.

IOW, your overcurrent protection likely resides at the primary
transformer
connection.....

Kapish ???

--

SVL

Partly true. The main breaker in the panel not only protects the panel
bus, it also provides a level of protection for the service drop by
disconnecting large faults from that service drop. The protection for
the drop itself is basically the fuse on the primary side of the utility
transformer which only has a chance of protecting the service drop in
the event of a dead short which might blow the fuse before the drop
melts.

Since the utility transformer is normally supplying multiple homes and
indeed the utility transformers are rated to handle a 100% overload for
24 hours without damage, it is entirely possible to overload and
incinerate the service drop without any harm to the utility transformer
or it's primary fuse.



Very good.

Now, suggest read NEC 230.9....because nobody here can give out the correct
answer until the service entrance conductor size has been determined.

--

SVL