OTIS elevator inverter OVF20

    First, the power supply of AC 380V-AC power supply or 220V AC power supply through a rectifier system of the inverter internal rectified into a DC voltage, and then loop through the inverter in the DC (direct current) voltage through the capacitor of the tributaries formation. 

    Use the pulse-width modulator inverter part of the rectifying out a DC voltage in the reverse into the frequency of the AC voltage can be changed to complete the inverter process. The OTIS elevator inverter OVF20. The first to see the circuit board in the front cover open OVF20, meaning of MCBII is Motion Control Board 2, Chinese meaning is the movement of the control panel, as the name implies, the control panel is the control of the movement as a whole system. This part of the course, all introduced in the first part of the interface, this refers to the board interface. The board is OVF20 the interface board for all of the input and output signals, and also dealing with these signal processing board. We can see the figure, in the elevator control cabinet speed command input to MCBII board by the elevator control system (LBII or LCBII or other control panel), MCBII board received the speed command with the the hoistway received signal (safety circuit, etc.), then MCBII issued within the inverter outputs a control signal to the inverter inside the transistor drive PDB plate, and finally completed by the PDB plate controls the inverter transistors to complete the inverter process. (Of the PDB plate is within the control panel of the inverter, is mainly used to control the inverter with high power transistor to complete inverter role, but the PDB is subject to MCBII control). MCBII command while in the receiving speed command and the hoistway, also receives a speed signal of the speed sensor PVT sent over, and comparing the internal set speed according to the actual speed of the elevator of this feedback to better control of the elevator operation. In the inverter circuit to the motor output, there are two phase line has two signal Feedback to MCBII of this is the current protection system of the inverter internal feedback through the output of the current sensor, can detect the output current of the inverter when found to exceed the rated output current, the inverter will protect off. In the inverter and also part of the brake resistor, which is partly used to brake the elevator.