| 摘要 |
<p>The alarm unit operates without electricity by using gas, e.g. aerosol, as the driving force. The alarm automatically switches itself off in normal conditions, while remaining ready for operation. In this state it is impossible for an unauthorised person to put it out of action before stealing the protected goods, or disconnect it, or try to disconnect it from the protected object at the beginning of such an action. The alarm, in such a case, delivers a loud signal. The alarm has a program control which programs both the alarm critical setting and the delay time between the alarm causing action and the actual tripping of the alarm signal.</p> |
