| 摘要 |
PROBLEM TO BE SOLVED: To store abnormal history information necessary for maintenance by providing a monitoring unit for always monitoring a voltage of a commercial power source, and immediately storing operation data at that time in a nonvolatile memory cell when a voltage is lowered to a predetermined value or below. SOLUTION: A power source 20 has a transformer 22 directly coupled to a commercial power source 18 through a primary side plug, and a first rectifier 24 interposed between a secondary side of the transformer 22 and a controller 12 in such a manner that the rectifier 14 and a second rectifier 26 are connected in parallel. A monitoring device for always comparing a voltage of 5VDC applied to a comparator 30 in the controller 12 with a reference voltage to monitor it is connected to the comparator 30 through the rectifier 26. A nonvolatile memory cell 34 is connected to the controller 12, and when the voltage is lowered to a predetermined value or below, the operation data at that time is immediately written in the cell 34. |
