| 摘要 |
<p>PURPOSE: To detect a fault condition in a wire with high reliability by applying a voltage pulse to any of outputs of transmitter units and providing a return bus to other outputs simultaneously. CONSTITUTION: A transmitter unit generates a periodic pulse to outputs 1-4 from a clock signal, a FET switch 24 is conductive in each low level output pulse from each OR gate 20 and a positive voltage pulse is fed to each output. When the output from the OR gate 20 is at a high level, a FET switch 26 is conductive and each output is connected to ground of the transmitter unit. That is, when a pulse is fed to any of outputs, other three outputs are connected to transmitter unit ground at all times. On the other hand, a receiver unit monitors a signal in each wiring and a return pulse is connected to at least other wire from each wire via a single direction current conduction device simultaneously. Thus, a means with reliability to check the wire is obtained.</p> |
