Patent ID: 7795827

Claim:
A control system for controlling a motor for a heating system, ventilation and air conditioning (HVAC) system, or a pump, the control system comprising: an opto-isolated speed command signal processing interface into which a signal for controlling a speed of the motor is inputted and which outputs an output signal for controlling the speed of the motor, the output signal having a specific single frequency; a communication device into which a plurality of operation control commands of the motor are inputted; an opto-isolated interface for isolating the plurality of operation control commands inputted through the communication device and the output signal for controlling the speed of the motor, respectively; a microprocessor, being connected to the opto-isolated interface, for outputting an output signal for controlling an operation of the motor depending on the plurality of operation control commands and the output signal for controlling the speed of the motor; a sensor, being connected to the motor, for outputting a rotor position sensing signal of the motor; a logic control circuit, being connected to the opto-isolated interface, the microprocessor, and the sensor, respectively, for using the rotor position sensing signal and the output signal for controlling the operation of the motor; a power switch circuit being connected to feed electric power to the motor; a gate drive circuit, being connected to the logic control circuit and the power switch circuit, respectively, for driving the power switch circuit; and a power supply device being connected to the logic control circuit, the power switch circuit, and the gate drive circuit, respectively, for feeding electric power thereto.