摘要 |
<p>Monitoring apparatus for redundant control systems includes means for preventing the monitoring apparatus from failing to a "good" state. Each of the channels in the redundant system generates a command signal which is compared to a signal provided by adding the command signal generated by another of the channels to a tracer signal. The amplitude of the addition signal is such so that the comparator toggles between its "good" and "fail" states to obviate failure of the monitoring apparatus to its "good" state.</p> |