Electrical system of Multistage Centrifugal Blower

Electrical system of Multistage Centrifugal Blower

1 General

The power supply is AC 380V, 50Hz, and the voltage of the control cabinet is 220V. The blower adopts variable (wide) frequency motor, which is controlled by frequency conversion cabinet; The field control cabinet of the blower is divided into two configurations: dynamic control cabinet (see Fig. 1) and PLC automatic control cabinet (see Fig. 2), and the local and remote control can be switched. The blower is also equipped with an audible warning light, which is placed on the top of the control cabinet. Meanwhile, the blower is equipped with an emergency stop switch for on-site emergency treatment.

                                            Fig. 1                                                                                                       Fig. 2                           

2 Blower variable frequency speed regulation start control

2. 1 Field manual control cabinet

First, confirm that the vent valve is fully open.

When the indicator light of the control cabinet and the blower indicator light are on, adjust the speed regulation knob to the minimum value, press the blower start button, observe the tachometer, adjust the initial start speed to 50rpm, and then gradually adjust the blower speed to 3550 RPM after a 3min interval. Gradually close the vent valve, observe the value of the pressure gauge, and fine tune the speed regulation knob until the required pressure is reached. Lock the speed regulation knob, turn the switch to the remote control gear, the blower operates at full pressure, and the adjustment is completed. If the vibration, temperature, current and voltage are observed closely during the acceleration, and abnormalities are found, if the temperature and vibration exceed the set value, the alarm light will light up, and please shut down in time.

Press the stop button to stop the blower. In case of emergency during operation, you can also press the emergency stop button. After troubleshooting, follow the above steps again.

2. 2 PLC automatic control cabinet

Confirm that the power supply of the control cabinet is normal, the vent valve is fully open, open the start button, start the touch screen, and conduct PLC program self-test. After the self inspection is completed without error, turn the control switch to the automatic control gear, and gradually raise the blower to the set value for full pressure operation. In case of manual vent valve, close the manual vent valve after the blower operates stably. The program has been set at the factory, and the parameters are fixed in place during installation and commissioning. Please do not modify the set parameters at will, otherwise the blower will fail.

3 Control of electric vent valve

If your blower is an electric vent valve, the control program has automatically completed the opening / closing of the valve.

4 Protection

The control cabinet is equipped with self-locking emergency stop button. In case of emergency, pressing it will stop all equipment controlled by the cabinet, and it can be reset by rotating in the direction of the arrow. The blower is equipped with temperature and vibration sensors and instrument display as standard. If the set alarm value is exceeded, the blower will give an alarm, and if the trip value is exceeded, the blower will automatically stop running.