Generator stopped producing electricity

If the generator has been sitting for a while you might have to excite the magnets to start producing power. plug in a reversible drill and with the generator running turn the drill in the reverse direction by hand while holding the trigger in the forward position.

Troubleshooting for generator no electricity output

Generator overheating
(1) The generator does not operate in accordance with the specified technical conditions, such as too high stator voltage, iron loss increases; if the load current is too large, the copper loss of the stator winding increases; if the frequency is too low, the cooling fan speed becomes slow, affecting the heat dissipation of generator; the power factor is too low, so that the rotor excitation current increases, resulting in the rotor heating. Check whether the indication of monitoring instrument is normal. If it is abnormal, necessary adjustment and treatment must be carried out to operate the generator in accordance with the specified technical conditions.

(2) The three-phase load current of the generator is unbalanced, and the overloaded one-phase winding will overheat; if the difference of three-phase current exceeds 10% of the rated current, it is a serious phase current imbalance, and the three-phase current imbalance will generate negative sequence magnetic field, which will increase the loss and cause heating of components of magnetic pole winding and hoop. The three-phase load should be adjusted to keep the phase current as balanced as possible.

(3) The air duct is blocked by dust accumulation, and the ventilation is poor, which results in the difficulty of generator heat dissipation. Dust and oil dirt should be removed from the air duct.

(4) If the inlet air temperature is too high or the inlet water temperature is too high, the cooler will be blocked. The inlet or inlet temperature should be lowered to remove blockages in the cooler. Generator load should be limited to reduce the generator temperature before failure is eliminated.
(5) Grease should be added to the bearing according to the regulations, usually 1/2~1/3 of the bearing chamber (the upper limit of the low speed, the lower limit of the high speed), and not more than 70% of the bearing room is suitable.
(6) Bearing wear. If the wear is not serious, the bearing is partially overheated; if the wear is severe, the stator and the rotor may be rubbed, causing the stator and the rotor to overheat. The bearing should be inspected for noise. If friction between stator and rotor is found, generator should be stopped immediately to repair or replace the bearing.

(7) The insulation of the stator core is damaged, which causes short circuit between the sheets, resulting in local eddy current loss and heating, and the stator winding will be damaged if it is serious. Machine should be shut down immediately for maintenance.

(8) The parallel wires of the stator windings are broken, causing the current of other wires to increase and heat up. The machine should be stopped immediately for repair.
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