摘要 |
<p>The emergency alarm has a sensor that is sensitive to a physical variable and has a signal processing circuit. The alarm communicates with a center either wirelessly or by a two-core cable, and its supply voltage is obtained from the center or from an attached battery by the two-core cable. A control circuit is provided that consists of NPN-transistors (T2,T3) with the collector connected on one side with the output of the signal processing circuit over resistors (R1-R7). The other side delivers the clocked control signal for the semiconductor switch depending on the voltage.</p> |