| 摘要 |
PURPOSE:To obtain the pressure monitoring device whose reliability in fault detection or prediction is higher, by monitoring the pressure (density) value as well as the temporal speed of change in the pressure (density) in a container. CONSTITUTION:When an arcing fault occurs and the internal pressure reaches a preset value PB, a switch SPB is actuated, and its contact signal is sent to a time counter circuit TM2 and to an alarm circuit AL. When the internal pressure is increased and reaches a preset point PC and a switch SPC is operated, a circuit TM2 stops the measurement of the elapse of time and sends a time signal DELTAt2, which represents the measured elapsed time, to a comparing circuit COM2. In the comparing circuit COM<2>, the signal DELTAt2 is compared with a reference value DELTAT2. When DELTAt2<DELTAT2 a locking signal is outputted, a corresponding breaker CB is operated through a trip circuit TR, and a faulty part is instantly isolated. When DELTAt2>DELTAT2, the fault is not serious, and it is judged that enough time is available for the action taken by the service personnel. Therefore only the alarm is indicated by an alarm circuit AL. |
