(under the class definition) Subject matter in which space discharge devices are connected in the armature or primary circuit of the motor and are connected so as to effect the commutation of the motor.
(1) Note. The interposition of an induction transformer or other electric converter between the space discharge devices and the armature of the motor does not prevent classification herein.
SEE OR SEARCH CLASS
315, Electric Lamp and Discharge Devices: Systems,
323, and subclasses specified in the notes for sequentially operated gas or vapor filled space discharge devices systems.
327, Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems,
518+, for miscellaneous electron discharge device control circuits.
363, Electric Power Conversion Systems,
166+, for electronic tube frequency converter systems.
388, Electricity: Motor Control Systems, art collections 913+ for other motor control systems utilizing space discharge devices in the control circuitry.