To solve a problem that a conventional power supply supervises an operating state of an inrush preventive circuit only indirectly, and an abnormality caused at malfunction in a relay contact is not detected, even if an auxiliary contact and a control portion are normal.
In a power supply, a magnetic field 30b generated by a current 30a flowing through a limiting resistor 30 is detected by a hall element 7, and if the magnetic field 30b is not detected by the hall element 7 when a capacitor 4 is charged, and if the magnetic field 30b is detected by the hall element 7 when a capacitor 4 is in a steady state, the power supply unit is constituted so that an abnormality detection circuit 6 may detect the abnormality of the inrush preventive circuit 3.
Hidetoshi Furukawa
Suzuki Kenchi
Kajinami order
Masahiro Taguchi
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