Supermarket door position indicator - has signaller connector to counter and loudspeaker providing different sounds for opening and closure

摘要

Monitoring of door opening in supermarkets or in similar places is ensured by a sensor connected to a loudspeaker system. Opening and closure of a door triggers audio signals of different frequencies as well as driving a counter. The resulting buzz or pip tones are not alarm signals but provide information to the supervising personnel. The door opening signaller (1) has an indicator (4) of the counter as well as an indicator (5) showing its operational readiness and an indicator (6) displaying the open position of the door. The loudspeaker (7) provides audio signals for closing and opening of the door.