摘要 |
A circuit for automatically shunting the field winding of a direct current motor and reapplying full field thereto. A low-level pull-in comparator compares a signal proportional to armature current to a low-level reference potential and causes the field to be shunted when the armature current signal falls below the low-level reference potential. A high-level drop-out comparator compares a signal proportional to armature current to a second independent high-level reference potential and causes the full field to be applied when the armature current signal is greater than the high-level reference potential. Prior to actuation, the pull-in comparator disables the drop-out comparator. Upon actuation, the pull-in comparator latches itself in actuated state and enables the drop-out comparator to be actuated. Upon actuation the drop-out comparator unlatches the pull-in comparator.
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