Either you have it plugged into an outlet that has too much currant draw on it, or you are using an extension cord that is too small of a gauge wire and it is overheating causing the breaker to trip. The other problem could be the motor is going bad.
The breaker should be sized to 250% of the motor's full load amperage.
Electric motor.
An electric motor converts electrical energy to kinetic energy.
In order for an electric motor to spin freely you will have to make sure you have one thing. You have to have the electric current for the motor to run freely.
The selection of overload protection for motors is taken from a table in the electrical code book. It is based on the full load current rating of the motor.
The circuit breaker is sized to the full load amps of the motor times 250%.
If there is nothing else on the circuit the odds are it kicks off when the compressor starts. This is a motor and the starting current is higher running current. The breaker senses this surge and trips. Either the compressor is drawing more current because of a problem with shunt somewhere in the winding of the motor or the breaker is tripping because it has a problem that has essentially made it more sensitive to current and is tripping on a lower current than it is rated for. The cheapest fix is to replace the breaker. If you know what you are doing you coudl just switch breakers with an equally rated breaker in the electric panel. If you don't know what you are doing find someone who does. If this doesn't fix the problem it is likely a faulty compressor.
Call an electrician; something in the furnace, possibly an electric motor, is using too much electricity.
If you put a 85 amp breaker in there it will overheat from the starting and stopping of the motor. The extra size of the breaker insures that the furnace will run without interruption and without overheating the breaker. And electric motor can draw three times the amperage rated on start up momentarily. This is why there is need of extra amperage ratings.
The breaker will blow because you are effectively causing a short circuit.
The motor winding has gone to ground internally. The ability of the motor to shock you is caused by the ground wire missing or not connected. It is this ground wire that trips the breaker in short circuit conditions and disconnects the motor from the distribution system.
Not a good idea in general. There is a large chance that you will trip what I expect is a 20 A breaker controlling the circuit. It may seem to work under some circumstances, but if the refrigerator compressor kicks in while the washer motor is demanding a surge current on motor start-up the breaker will likely trip.
The wiring is like this:[[30KW Motor ---- Star Delt Starter(100A Breaker inside) ----- 200A Breaker------50A Breaker(Inside the breaker box which located inside the factory) -----100A Main Breaker]]Once I try to start the Motor, the Main Breaker trips immediately.
One window, probably the switch or the electric window motor. All windows, probably the fuse or circuit breaker.
Check your Delta connections first if the phases is corresponding, and check your Circuit Breaker if it sufficiently rated.
The electric motor changes electric energy into mechanical energy.
An electric motor