摘要 |
An output circuit with a controller and intelligent output stages for process control where the output stages are supplied with power from separate voltage sources which are electrically separated from each other. The actuating commands from the controller for semiconductor switches in the output stages and feedback signals to the controller from the output stages are carried back and forth via optical couplers. Each output stage receives its own direct current supply, which is obtained by rectifying a chopper current supply. The feedback signals are transmitted serially being clocked by pulses derived from the chopper current supply. Thus, actuating commands may be issued without retrospective effect. Switching operations may be carried out during the process. Diagnostic signals concerning the load current circuit can provide feedback efficiently.
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