| 摘要 |
<p>A method and apparatus for generating an alarm signal upon detecting movement of an object over a time that is greater than a field settable allowed movement time. The method includes the steps of locating a housing with respect to the object, setting the allowed movement time for the object, monitoring the movement of the housing, detecting a movement that exceeds the allowed movement time of the housing, generating an alarm signal, and transmitting by wireless transmission the alarm signal to a remote receiving station. Setting the movement time for the object is achieved by the following steps: powering the apparatus while depressing a tamper switch, initiating a time counter, moving the object an acceptable distance, releasing the tamper switch, stopping the time counter, and reading the allowed movement time from the time counter. Detecting a movement greater than the allowed movement time includes the steps of detecting a movement of the housing, enabling an allowed movement time counter to count down the allowed movement time, enabling a restore counter to count down a restore time, detecting movement of the housing during the restore time, allowing the allowed movement time counter to continue to count down the allowed movement time, and determining when the allowed movement time counter has completed counting the allowed movement time.</p> |
