| 摘要 |
PURPOSE:To detect an overcurrent in an efficiency adapted for a state of a using load by automatically setting a current limit value adapted for the load at each predetermined time, and detecting the overcurrent with the set limit value as a reference. CONSTITUTION:A load current is detected by a current detector 11, and converted to a digital value I by an A/D converter 12. A microcomputer 14 reads a detected load current value from the converter 12 n times at each predetermined time interval, and decides a current limit value. Then, the microcomputer 14 reads a detected load current value, and checks whether the detected value exceeds the limit value or not. If the microcomputer 14 judges the flow of the overcurrent, it again reads the detected value after a predetermined time, and checks whether the read detected value exceeds the limit value or not. |
