Microwave fuse service — if house breaker trips on microwave start, severe short circuit inside. Usually magnetron shorting to ground, burnt HVT, or bad HV capacitor. Severe danger — don't use until diagnosed.
See if any of these signs match your device — each one increases the likelihood of this fault.
These are the causes we encounter while repairing House fuse trips on microwave — ranked from most to least common.
Magnetron shorting to ground
Burnt high voltage transformer (HVT)
Bad high voltage capacitor
Burnt high voltage diode
Worn internal wiring
Door switches shorting
Any of the following = a danger signal — call now and don't try to fix it yourself.
On-site diagnosis, clear pricing before any work, and a documented 6-month warranty.