| 摘要 |
PROBLEM TO BE SOLVED: To detect a failure of semiconductor relays connected in series with a simple circuit by connecting the semiconductor relays in series to reduce a failure rate to short-circuit side. SOLUTION: Semiconductor relays 321 and 322 are connected in series so that, even if either one of the semiconductor relays 321 and 322 fails by a short- circuit, the output 341 cannot be erroneous. Also, any failure of the semiconductor relays 321, 322 are diagnosed by connecting the semiconductor relays 323, 324 to the input side of the semiconductor relays 321, 322. By connecting an output cutting relay 332 to the output side, an output is cut when a failure was detected. |
