Symptoms
- Breaker trips as soon as an appliance is plugged in
- Breaker trips only when a specific device starts up
- Generator runs fine with nothing connected
- Breaker won't stay reset at all
Likely causes
- CommonTotal connected load exceeds the generator's rated wattageAdding up the running watts of everything plugged in, plus the startup surge of motors, easily exceeds a generator's capacity.
- CommonHigh-surge appliance startup (fridge, AC, power tools)Motors can draw 2–3 times their running wattage for a second or two at startup, which can trip a breaker even if the running load is fine.
- PossibleFaulty extension cord or connected appliance with a shortA damaged cord or device can cause a real short that legitimately trips the breaker.
- PossibleWorn or failing breaker on the generator itselfBreakers can weaken with age and trip below their rated threshold.
What to do
- Unplug everything and reset the breaker, then add devices back one at a time, noting the wattage of each.
- Add up the running and startup wattage of everything you intend to run, and compare it to the generator's rated wattage from its label or manual.
- Prioritize essential appliances and stagger startup, turning on one motor-driven device at a time rather than all at once.
- Inspect extension cords and plugged-in devices for damage, and try a different cord or device to isolate a short.
- If the breaker trips even with a light, single-device load well under rated capacity, the breaker itself may be failing.
- Avoid running space heaters or other very high-draw resistive loads alongside motor-driven appliances.
- If the breaker seems to trip below its rated capacity consistently, have a small-engine or generator repair shop test and replace it.
Tools and parts
- None required for basic checks
Generator circuit breakerSearch: “portable generator circuit breaker replacement”
When to call a pro
If the breaker trips well below the generator's rated capacity, have it tested and replaced by a repair shop rather than continuing to reset it repeatedly.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.