Overvoltage of the capacitor can occur when:
- the generating set’s engine speed is too high
- a too heavy load is turned off. This causes the engine speed to briefly increase too much. Then, the voltage on the stator’s secondary winding of the single-phase alternator to which the capacitor is connected, increases too much as well
- a welder is connected to the generating set
When connecting a load to the generating set, it is important to bear in mind the generating set’s nominal power as well as the appliance’s nominal power.
Other less common causes of broken capacitors are:
- excessive vibrations on the capacitor
- too high temperature (insufficient or bad cooling of the alternator/generating set)
- “worn out” capacitor (the normal lifespan of a capacitor lies near 2500 – 3000 running hours)