Abstract: A method of controlling operation of a multi-phase induction motor may include transmitting a low-speed operation signal by a master computer to a control signal board for low-speed operation of the motor; the control signal board receiving the low-speed operation signal, and in response to the low-speed operation signal, the control signal board sensing that the master computer is not simultaneously transmitting a high-speed operation signal, and in response to receiving the low-speed operation signal and not simultaneously receiving the high-speed operation signal, closing contactors in a power section to transmit power to the motor for low-speed operation, whereby the motor is connected to a source of multi-phase power and operates at low-speed; and the control signal board transmitting a first feedback signal to the master computer that the motor is connected to the source of multi-phase power and is running at low speed.

Abstract: A method of controlling operation of a multi-phase induction motor may include transmitting a low-speed operation signal by a master computer to a control signal board for low-speed operation of the motor; the control signal board receiving the low-speed operation signal, and in response to the low-speed operation signal, the control signal board sensing that the master computer is not simultaneously transmitting a high-speed operation signal, and in response to receiving the low-speed operation signal and not simultaneously receiving the high-speed operation signal, closing contactors in a power section to transmit power to the motor for low-speed operation, whereby the motor is connected to a source of multi-phase power and operates at low-speed; and the control signal board transmitting a first feedback signal to the master computer that the motor is connected to the source of multi-phase power and is running at low speed.

Abstract: A method for controlling operation of a multi-phase induction motor may include transmitting a high-speed operation signal by a master computer for high-speed operation of the motor; receiving the signal by a control signal board, and in response to the signal, the control signal board may sense that the master computer is not simultaneously transmitting a low-speed operation signal, and in response to receiving the high-speed operation signal and not simultaneously receiving the low-speed operation signal, closing delta-to-wye contactors and closing contactors in a power section to transmit power to the motor for high-speed operation, whereby the motor is connected to a source of multi-phase power and operates at high-speed; and the control signal board transmitting a first feedback signal to the master computer that the motor is connected to the source of multi-phase power and is running at high speed.

Abstract: A method and system for controlling operation of a multi-phase induction motor may include the steps of transmitting a signal by a master computer to actuate a first switch for high-speed or low speed operation of the motor, receiving the signal by a control signal board, and in response to the signal, the control signal board may determine that the motor is enabled for high-speed operation and disabled for low-speed operation, or enabled for low-speed operation and disabled for high-speed operation, as the case may be. In response to the motor state, the control signal board may close or open delta-to-wye contactors, then transmit a signal to a power section to close power contactors to connect the motor to a source of multi-phase power.