12V (via ignition switch ) The action of the circuit is such that the relay is normally off, but turns on when the voltage on the ... Relay-output low-fuel-level alarm, positive-ground Figure 7.1 Precision d.c. over-voltage alarm, covering 5 V upwards.
|Title||:||Electronic alarm circuits manual|
|Author||:||R. M. Marston|
|Publisher||:||William Heinemann Ltd - 1988-12|