| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent damage to an erroneously connected voltage monitoring apparatus (for example a voltage monitoring transformer). <P>SOLUTION: When a commercial power supply unit 15 converts generated DC power into AC power and outputs the power, a T-phase system voltage detection/cut-off circuit 31 and an R-phase system voltage detection/cut-off circuit 32 operates in conjunction with a controller 20 to monitor the voltage on a commercial power line; if the voltage on the monitored commercial power line exceeds a prescribed voltage, a relay 31A or a relay 32A cuts off the supply of commercial power to voltage detecting transformers 31B, 32B, or disconnects the voltage detecting transformers 31B, 32B electrically from the commercial power line. <P>COPYRIGHT: (C)2004,JPO |
