Alarm device with integrated function test device, e.g. for building fire alarm or vehicle burglar alarm, includes primary detector, specifically as electrodynamic acoustic transmitter, and microphone as check-back device

摘要

The alarm device having a primary detector and a check-back device which receives a signal from the primary detector and relays or processes it. The primary detector outputs acoustic or optical signals and the check-back device comprises a microphone or a light sensor.