1. Before starting the test, check:
- generator installation;
- battery charge level (battery must be fully charged);
- alternator drive belt tension;
- fusible insert;
- the absence of extraneous noise from the generator when the engine is running.
2. Turn the ignition key to position «OFF» («OFF»).
3. Disconnect a wire from the negative plug of the storage battery.
Pic. 9.3. Voltage regulator test circuit: 1 - rechargeable battery; 2 - ignition switch; 3 - red wire; 4 - blue wire; 5 - voltmeter; 6 - generator; 7 - ammeter; 8 - connection point of the tester with a standard wire
4. Connect a digital voltmeter between the terminal «S» generator and «weight» (connect lead «+» voltmeter to output «S» generator, and then connect the output «–» voltmeter to «mass» or to the negative terminal of the battery) (pic. 9.3).
5. Disconnect the standard wire from the output «IN» generator.
6. Connect a DC ammeter with a measuring range of 0-100 A between the terminal «IN» generator and disconnected regular wire (connect lead «+» ammeter to output «IN» generator, and the output «–» ammeter terminals to the disconnected standard wire).
7. Connect a tachometer.
8. Reconnect the wire to the negative battery terminal.
9. Turn the ignition key to position «ON» («ON») and check that the voltmeter reading is equal to the battery voltage.
Attention! If the voltmeter shows 0 V, then an open circuit is likely between the output «S» alternator and positive battery terminal.
10. Turn off all lighting and additional electrical equipment of the car.
11. Start the engine.
12. Increase the engine speed to 2500 min-1.
13. Read the voltmeter reading when the generator output current is less than 10 A.
If the voltmeter readings correspond to the nominal values \u200b\u200bof the regulated voltage, the voltage regulator is working.
If the voltmeter readings do not correspond to the range of nominal values, either the voltage regulator or the generator is faulty.
14. After the end of the test, let the engine idle.
15. Turn off the ignition.
16. Disconnect a wire from the negative plug of the storage battery.
17. Disconnect the voltmeter, ammeter and tachometer.
18. Connect the standard wire to the output «IN» generator.
19. Connect a wire to the negative plug of the storage battery.