| 摘要 |
<p>Monitoring apparatus is for monitoring a parameter, such as a drive current to a motor. Motor current flows through a series resistor which provides a voltage signal which varies in response to variations in the motor current. An analysis circuit is operable to analyze the rate of change of the voltage and to provide an alarm signal in the event that the rate of change continues in excess of predetermined rate for a period in excess of a predetermined time. The alarm signal could, for example, be used to indicate that an automatic door being driven by the motor has been blocked by a person or object which could be injured or damaged.</p> |
