OP
MikeP
Exactly!
the hold-off voltage is applied to the siren's control electronics, (used to be a relay in ancient days), if the voltage is removed or disconnected, (Burglar Bill severs the bell wire), there is an integral ni-cad in the siren unit which provides energy for the sounder to work. Opening the tamper switch on the unit, (removing the cover or levering the unit from the wall), has the same effect.
For a thorough understanding of the siren unit consider developing a wiring diagram from first principles using a change over relay.
MikeP
the hold-off voltage is applied to the siren's control electronics, (used to be a relay in ancient days), if the voltage is removed or disconnected, (Burglar Bill severs the bell wire), there is an integral ni-cad in the siren unit which provides energy for the sounder to work. Opening the tamper switch on the unit, (removing the cover or levering the unit from the wall), has the same effect.
For a thorough understanding of the siren unit consider developing a wiring diagram from first principles using a change over relay.
MikeP
