| 摘要 |
PROBLEM TO BE SOLVED: To prevent misjudgment for open/short of a load by, after a load control means outputs a first driving signal, letting a first specified time pass before a second driving signal is output. SOLUTION: When a microcomputer 7 receives a load communication start signal form an operation switch 1, the microcomputer 7 sends an energization signal to a transistor 3, and the electromagnetic coil 21 of a DC relay 2 is brought in conduction and turns on a contact 22. Whether a timer reading T has exceeded a first specified time t1 sufficient to cope with electromechanical delay in the contact operation of the contact 22 of the DC relay 2, is judged in a specified cycle. If it is judged that the first specified time t1 has been exceeded, the microcomputer 7 sends a signal to a switching transistor 4 and turns on the switching transistor 4 to cause the switching transistor 4 to start the energization of a load. In addition, whether a timer reading T has exceeded a second specified time t2 sufficient to cope with a delay of inrush current in returning to a stable range, is judged in a specified cycle. If it is judged that the second specified time t2 has been exceeded, the mode at the time of energization start is finished and the mode is shifted to the ordinary operation mode. As a result, misjudgment in detecting a fault of the load can be prevented. |
