Dishwashers are extremely convenient appliances to have in the kitchen. When they are working properly, they save you the effort of scrubbing dishes by hand in a sink full of hot, soapy water. Just load them up, press the "On" button and go about your day. However, when the dishwasher trips the circuit breaker each time you run it, then it isn't really much of a convenience. There are a few reasons why this type of problem can occur.
When a motorized appliance such as a washing machine is plugged into a GFCI outlet, it can sometimes cause the circuit to trip and shut down the machine. GFCI, or ground fault circuit interrupters, are designed to shut down when they sense a circuit overload. They are somewhat unstable and may trip too easily when hooked up to an appliance such as a dishwasher. Wiring the dishwasher in directly or plugging it into a regular outlet is a better option to prevent this problem.
Power Cord Problems
If your dishwasher is regularly tripping the circuit breaker when it runs, then you should pull out the dishwasher and thoroughly inspect the power cord. If the power cord has a short or has exposed frayed wires, it could cause the overload and resulting tripped breaker. A faulty power cord could also be an electrical and fire hazard, and it should be replaced or repaired.
Faulty wiring can cause the circuit breakers to trip when the dishwasher is started up or while it is running. If the wiring to the machine has burned or damaged wires that are not making a clean connection, it could cause sparking, fire hazards and power surges that can trip the circuit. Have a qualified electrician take a look at your dishwasher's wiring to make sure it is safe and operating properly.
Humidity or Water
Humidity produced by the dishwasher or leaking water can make an outlet trip the circuit breaker while in use. Regular outlets may spark when they get wet and result in a trip. GFCI outlets may kick off instantly to prevent any real damage when moisture is present. If the dishwasher is physically close to the breaker box, the moisture could cause it to trip directly.
It is possible that your dishwasher is simply connected to a bad circuit breaker. The power getting to the actual assigned breaker may not be adequate. The breaker itself could be faulty. Check to see if it flops back and forth and is difficult to lock into the "On" and "Off" positions. If it is, it needs to be replaced. Check for corrosion or signs of blackening from overheating and burning.