"Tom" wrote in message
newsk7gd.321434$MQ5.224771@attbi_s52...
I have a Sears 25 gallon/4HP horizontal compressor. When I first turn it
on
it runs fine and shuts off at 150psi. The problem I have is when the
pressure gets at the level where it automatically kicks on again it then
pops the breaker off and I then have to reset the breaker before it will
run
again. I have a dedicated 20 amp circuit with 12/2WG using a Square D
breaker and a 20 amp duplex receptacle for the compressor, and nothing
else
is on this circuit. Do any of you folks have any suggestions as to how I
can
cure this problem? Thanks for your help.

You do not mention the distance the circuit is. I assume you ran #12 copper?

Have you checked the connections on the breaker and recpt. An motor can draw
6 times FLA on start up. With an air compressor with partical pressure the
high current draw could be lasting longer than the breaker likes.

Try changing breakers with another in the panel. If it still happens then
check out the compressor.