摘要 |
A d.c. motor, particularly a paper-feed drive motor for printers, is monitored and controlled (e.g., for protection against paper jamming) by controlling a motor switch to turn the motor off temporarily when excess current is monitored, but turning it on to probe persistence of the condition. This turn-on will remain short if, indeed, overload current conditions are still present. The circuit includes a bistable multivibrator with input circuit rendering it monostable for normal operating conditions and astable for the overload case.
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