MONITORING DEVICE FOR POWER SUPPLY TRANSFORMER ROOM

PROBLEM TO BE SOLVED: To obtain stable power supply to a multiple dwelling house, such as the menshion, etc., by installing a power supply device to the power supply transformer room of the house and to make a countermeasure to be taken quickly when an abnormal status, such as the overcurrent, etc., occurs due to a power failure or short circuit on a power supply transformer side by transmitting an alarm signal to the center side of the house. SOLUTION: A current transformer 1 is connected to the secondary-side cable of a power supply transformer and the output of the transformer 1 is sent to a rectifier 4 for rectification through an overvoltage suppressing circuit 3. Then a voltage stabilizing circuit 5 stabilizes the output voltage of the transformer 1 and supplies the voltage to a load 6. In addition, a comparator circuit 11 monitors the output voltage of the transformer 1 and, when the voltage gets out of a prescribed voltage range preset to a threshold setting circuit 14, the circuit 11 interrupts the input of the power supply from the transformer 1 by operating a relay 13 by outputting a contact operating signal from a contact output circuit 12 and outputs a signal indicating the occurrence of abnormality to a monitoring device.