Relay winding (with the generator running) is under the rectified phase voltage of the generator If the voltage between the terminal "30" of the generator and the "ground" is 13.8-14.5 V, the rectified phase voltage is 5-7 V.
The relay contacts close the power supply circuit of the control lamp 6 (fig. 7-5). When the ignition is turned on, when the engine (and therefore the generator) it doesn't work yet, current from the battery flows through the contacts. The lamp is on.
After starting the engine and when the car is moving, the lamp should go out, since under the action of the rectified phase voltage, the relay anchor should be attracted to the core and open the relay contacts.
If the control lamp does not go out after starting the engine and while the car is moving, this indicates a malfunction either in the generator or voltage regulator, or a malfunction of the relay itself (winding breakage, etc.).
Data for verification
- Contact opening voltage, 13 V — 5.3±0.4
- Contact closing voltage,* V — 0.2-1.5
- Winding resistance at 20°C, Ohm — 29±2
* At a temperature of 25±5°C
[The original is posted on Internet resource VAZbook.ru]