1. Leave the generator running and use a voltmeter to test the battery. The voltage displayed at this time should be around 13 volts or a little more if different speed changes cause the voltage to fluctuate between 13 and 14 volts, then the generator is in good condition; on the other hand, if the voltage remains the same or decreases, then the generator is indeed defective;
2. Start the engine, turn it off after a few minutes and touch the generator. If the generator is very hot, the bearings may have worn out or the insulating copper windings may have been damaged, indicating. that the generator will soon be out of service.
3. Turn on the radio and start the engine. If the radio vibrates or the sound quality is fuzzy every time you step on the accelerator, there is probably a problem with the generator.
4. When the car does not start, use an electric meter to measure the V number of the battery and record iter. Then start the car, use the meter to measure the battery V number and record it. If the car's alternator is not broken, the battery's V number will be higher when the car is started. Around 13.7V, depends on the car. But it will definitely be higher than the V number where the car will not start. The most obvious thing is that if the generator fails and the car is driven for 2-3 days, the battery will lose power and the car will not be able to start on electricity.
5. Turn on the car headlights, check the brightness of the lights, then start the car. The lights will dim and the car will start. Check the headlight brightness, then increase the throttle and check the brightness. If there is not a big difference between the lights before starting and after starting, it means the generator is not working. If the lights before and after startingare reflected and become very bright, then the generator is working fine but the battery is defective.
The generator does not operate according to the specified technical conditions. If the stator voltage is too high, iron loss increases; the load current is too large, the copper loss of the stator winding increases; low, causing the cooling fan speed to slow down, affecting the heat dissipation of the generator; the power factor is too low, which increases the rotor excitation current and causes the rotor to heat up. Check whether the monitoring instrument indication is normal. If this is abnormal, necessary adjustments and treatments should be made to operate the generator according to the specified technical conditions.
Reference materials:
Car generator - Baidu Encyclopedia