Precautions when repairing a generator (VAZ-2121)

1. The "minus" of the battery must always be connected to the "ground", and the "plus" must be connected to the "30" terminal of the generator. Incorrect reverse connection of the battery will immediately cause an increased current through the generator valves and they will fail.

2. It is not allowed to operate the generator with consumer wires disconnected from terminal "30" (especially with the battery disconnected). This causes a dangerous increase in voltage on the valves, and they can be damaged.

3. It is prohibited to check the generator's performance "for a spark" even by briefly connecting the generator's clamp "30" to the "ground" or plug "67". In this case, a significant current flows through the valves and they are damaged. The generator can only be checked using an ammeter and voltmeter.

4. It is prohibited to check the charging current circuits with a megohmmeter or a lamp supplied with a voltage of 36 V. If such a check is necessary, then the wires from the generator and voltage regulator should first be disconnected.

5. The strength of the stator insulation should be checked with increased voltage only on a test bench and necessarily with the phase winding terminals disconnected from the valves.

6. The wire connected to the generator plug "67" should not be confused with the wire connected to the star point terminal plug (plug without marking). If you mistakenly swap the wires, fuse 10 will burn out (fig. 7-1) and the voltage regulator contacts will be damaged.

7. When electric welding vehicle body components and parts, disconnect the wires from all terminals of the generator and battery.

8. Generator valves should never be tested in a circuit with an alternating current of 110 and 220 V or more, even if there is a signal neon lamp, and should not be tested with a megger, since it has too high a voltage for the valves. In these cases, the valve will be broken during testing (a short circuit will occur).