| 摘要 |
PURPOSE:To simplify measurement by incorporating a means driving a power supply optionally in a recording body and displaying the measured current of the recording body. CONSTITUTION:If switches 400, 408D are turned on when drum current applied to the operation of a charging part 104 is to be measured, all high voltage power supplies 216, 218, 220 are driven. Consequently, the charging part 104 is actuated, a current flows between a measuring tool 16 and the earth and a part of the current is inputted to an A/D converter 410. A digital signal from the A/D converter 410 is inputted to a decoder drive 412 and a drum current value is displayed on a display panel 506. When the drum current applied to the operation of a transfer part 112 is to be measured, the switches 402, 408D are turned on and the high voltage power supply 218 is driven. When the drum current applied to the operation of a separation part 114 is to be measured, a DC component is measured by turning on the switches 404, 408D and an AC component is measured by turning off the switch 408D and turning on a switch 408A because the DC component of corona discharge is superposed to the AC component. In such a procedure, the drum current is measured rapidly and precisely. |
