Electronic bistable impulse relays enable switching on or off lighting or other device from several different points by means of parallel connected, momentary (bell) control switches. The receiver is switched on after a current pulse caused by pressing any momentary (bell) button connected to the relay. After the next pulse, the receiver will turn off. The relay does not have a "memory" of the contact position, i.e. in the event of a power failure and its return, the relay contact will be switched off. This makes it impossible to automatically turn on the controlled receivers without supervision after a long-term power failure.