Hi folks

I have a problem with my dryer. Putting the dryer on will
intermittently flip the main circuit breaker. There doesn'tseem to be
a particular pattern - the dryer would run for sometime and then cause
the main circuit breaker to flip. The dryer is a maytag 120V/240V
three prong 5600 watts machine. It is on it's own circuit with a 30+30
amp breaker but this breaker neever flips.

My daignosis till now is that when the dryer is on and any other
appliance switch on (even a light bulb) will cause the main breaker to
flip. That would point to a faulty main breaker. Hoever it can be
something else. Is there a 3 phase thing going on for this 240 V
supply ?

Suggestions are welcome. Is replacing the main breaker a very
expensive proposition, since I am not very keen on doing it myself ?

Regards
Debjyoti