| 摘要 |
PURPOSE:To effectively prevent an erroneous operation even if an undefinite output is generated due to the calculating malfunction of a main detection relay by allowing a fail-safe relay to inspect only when the main detection relay normally runs and the fail-safe relay receives an automatic inspection command. CONSTITUTION:When the calculating function of a main detection relay 1 malfunctions due to the runaway of a CPU 3, the CPU 3 does not normally process a programming. Accordingly, running monitor processing means 30 generates no output, normal running discriminating means 31 output a signal of logic '0' with no output of the means 30, and condition discriminating means 33 stops outputting an automatic inspection enable signal. |
