(under subclass 705) Subject matter which includes means responsive to the loss of synchronism in the motor to control the circuit connected to the field winding of the motor to cut the DC power to the field winding of the motor.
(1) Note. Subject matter of this subclass type not only removes the DC power from the field winding but can also reapply the DC power to the field winding.
SEE OR SEARCH THIS CLASS, SUBCLASS:
536+, and the subclasses specified in the notes thereto for other motor control systems in which the field circuit is made and/or broken.
712, for synchronous motor synchronization systems to apply the DC field to a synchronous motor.
716, for field circuits of synchronous motor systems where the power to the circuit may be switched on or off.
