| 摘要 |
<p>PROBLEM TO BE SOLVED: To simplify the circuit constitution by providing a test pulse generating circuit which logically adds or subtract a test pulse having a time length less than a specific ratio of the response time of an actuator to or from a control signal and allowing a judging circuit to judge within the time of the addition or subtraction of the test pulse. SOLUTION: To conduct a test, a test pulse generating circuit 8 outputs an ON test pulse (short time) and the output is inputted to an AND logic gate 7 through a capacitor 10 to turn off a power transistor 6 for the time length of the test pulse irrelevantly to the output of a logic circuit 2. This is detected by a current pick up 13. The time length of a short-time pulse is only <=1/3 time as long as the response timeτof the actuator 3 (e.g. 1 mS), so the actuator 3 never responds to the pulse. Then the decision circuit 31 decide whether or not the circuit is normal in the short time of the output of the test pulse.</p> |
