Microwave tripping the circuit breaker? How to fix

1) Introduction: Why Does This Keep Happening?

​If your microwave keeps tripping the circuit breaker then there is an electrical fault that needs some investigation. It is important to understand that continually resetting a breaker that trips will cause further damage beyond any damage that has already been caused. A microwave oven is an appliance that is generally reliable but occasional electrical problems can result in breaker trips.

2) Understanding Circuit Breakers and How They Work

​A circuit breaker is a switch in the electrical panel or consumer unit that protects an electrical circuit. Its purpose is to prevent overload, damage from short circuit problems and to protect the cables and connected equipment on the circuit. A tripped breaker means that there is a problem that requires fixing along the circuit somewhere. In some cases, the breaker itself can be faulty resulting in early tripping. 

3) Common Reasons Your Microwave Trips the Breaker

​A faulty microwave could be the reasons for the tripping circuit breaker. If you suspect that the microwave may be faulty then try using a socket outlet on a different electrical circuit to see if a different breaker trips. 

An overloaded circuit breaker could be the cause of the tripping. If the microwave is on a dedicated circuit (only powers that appliance) then check the rating of the breaker to ensure that it is not overloaded. Compare the rating of the circuit breaker to the microwave's power demand. 

​A faulty electrical cord to the microwave could easily be the culprit. Check the condition of the flex cord to the microwave and ensure there is not a damaged power cord. Inspect the plug, the lead, and the point of entry to the appliance for visible signs of damage. Also check that the socket outlet is not burnt or melted

Damage on the electrical circuit or faulty wiring could also mean that the microwave trips the breaker. Try the microwave in different electrical outlets to see if the problem happens each time.

4) Overloaded Circuit: Too Many Appliances, Not Enough Power

When a circuit is overloaded, power levels being demanded are beyond what the circuit breaker will allow. This is because the electrical circuit cable cannot cope with such high power demands and the breaker steps in to disconnect the circuit and prevent damage. Try unplugging some of your heavy load appliances and then using the microwave again, if the breaker trips then it is not due to overload.

5) Microwave-Specific Issues That Cause Trips

A microwave has various internal components that can fail. If any of these internal components or internal wiring short out, then this will lead to a breaker tripping. Think back and try to remember if the appliance has been dropped, if anything has been spilled into the microwave or if anything else may have affected it? 

How old is the microwave? Older microwaves are more likely to break down and cause breaker problems. The home's electrical system is very good at disconnecting the power when there are power surges, short circuits, or faulty appliances but it’s not very helpful at telling you what the exact problem is. You may need a professional technician to examine the appliance and determine if it has gone faulty. 

6) GFCI and AFCI Breakers: Special Cases That Could Be the Culprit

If the microwave is installed on a GFCI or AFCI breaker then any small issue with the appliance or wiring on the circuit could cause the breaker to trip. These types of breakers are very sensitive to electrical problems and will detect many different things! A Ground Fault Circuit Interrupter or Arc Fault Circuit Interrupter installed at your outlets or in the breaker box is likely to trip regularly if electrical appliances are beginning to turn faulty. 

7) 7. Bad Outlet or Wiring Problems

Occasionally a loose wire in an electrical outlet can be the root of the problem. When wires work loose, they can touch other wires and result in earth faults or short circuit problems. A failing outlet can result in poor electrical insulation between wiring and trip out a breaker when a significant amount of power is being used (such as a microwave). Check the power outlet for any visible signs of damage and have an electrician replace it if necessary. Try using a different appliance in the outlet that has a high power consumption like an electric heater for example. If the breaker also trips with the heater in use, then it’s not likely the microwave is faulty. 

8) When to Call a Professional

Where electrical issues are recurring, calling a professional electrician to examine the causes is the best way forward. There are a number of possible causes for a circuit breaker that is tripping and whilst it may appear to be the microwave that is causing the issue, there may actually be an unrelated cause somewhere else in the homes electrical system such as faulty wiring.

9) Preventing Future Breaker Trips

If you find that appliance breakers are tripping frequently then it may be as a result of too much power demand. Seek professional help from a certified electrician as it may be necessary to have a dedicated circuit for each large, power hungry appliance. This is especially true for electrical cooking equipment like ovens and stove tops which should have their own dedicated circuit. The electrical supply in our homes needs to be sufficient for all the equipment we intend to use and without an adequate power supply, circuit breaker trips are an increasingly likely result. 

10) Conclusion: Don’t Ignore the Signs

Don't rush out and buy a new microwave just yet, ensure that you have done all the checks that you can before committing to purchasing a new microwave. If you cannot identify the root cause of the problem then consult with an electrician to ensure that there are not issues with the breaker panel, wiring, or socket outlets. Many electricians can test an appliance for electrical faults as well so it’s worth having a chat with one before making any new appliance purchases.