A protection circuit for protecting a load, such as a winch motor, from an overcurrent as well as from a circuit fault including welded primary switch contacts and a failure of its MOS/FET component. A power MOS/FET is used as a current mirror for sensing load current. A secondary switch is series connected to control the primary switch. A control circuit including a programmable data processor controls the MOS/FET and the secondary switch and senses the current through the MOS/FET's secondary source terminal and senses the voltage at its primary source terminal. The programmable data processor determines whether an overcurrent exists by comparing the sensed power circuit current to a stored overcurrent value and also senses whether the contacts of the primary switch are welded closed and whether the MOS/FET has been damaged. Additional conditions are sensed. Application of power to the load is prevented when such conditions are detected.
Winch motor protection circuit
2021-03-23
Patent
Electronic Resource
English
IPC: | G01R Messen elektrischer Größen , MEASURING ELECTRIC VARIABLES / H01L Halbleiterbauelemente , SEMICONDUCTOR DEVICES / H02H EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS , Schutzschaltungsanordnungen / B66D Haspeln , CAPSTANS / H02J CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER , Schaltungsanordnungen oder Systeme für die Abgabe oder Verteilung elektrischer Leistung / H02P CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS , Steuern oder Regeln von elektrischen Motoren, elektrischen Generatoren, dynamoelektrischen Umformern / H03K PULSE TECHNIQUE , Impulstechnik |
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