Multimotor variable frequency overload

摘要

An apparatus for protecting a motor includes two or more motor overloads, within a motor overload enclosure, protecting two or more motors. Each motor overload includes one or more current sensors where each current sensor includes a magnetic core and each current sensor includes a conductor positioned within the magnetic core where the conductor providing power to a motor protected by the two or more motor overloads (“protected motor”). Each motor overload includes a motor trip module that stops current flow to the protected motor in response determining that a thermal state of the protected motor has reached a thermal limit. Determining that the protected motor has reached a thermal limit includes using a current signal from at least one current sensor of the one or more current sensors that senses current of the protected motor to determine a thermal state of the protected motor.

主权项

1. An apparatus comprising:
a motor overload enclosure; and two or more motor overloads protecting two or more alternating current (“AC”) motors, each motor overload of the two or more motor overloads located within the motor overload enclosure, each of the two or more motor overloads being external to an enclosure housing a motor of the two or more motors, each motor overload comprising
one or more current sensors, each current sensor comprising a magnetic core, each current sensor comprising a conductor positioned within the magnetic core, the conductor providing power to a motor protected by the two or more motor overloads (“protected motor”); anda motor trip module that stops current flow to the protected motor in response determining that a thermal state of the protected motor has reached a thermal limit, wherein determining that the protected motor has reached a thermal limit comprises using a current signal from at least one current sensor of the one or more current sensors that senses current of the protected motor to determine a thermal state of the protected motor, wherein the two or more motors are controlled by a single motor controller, wherein each output conductor of the motor controller is divided to feed each of the two or more motors.