Measures and characteristics of protection and control for screw air compressors

1. What are the protection and control measures for screw air compressors?

There are two types of protection and control measures for screw air compressors: single machine protection control and joint control protection control system.

Single machine protection control is a control system for each air compressor, which controls the various protection settings of the single air compressor.

Joint control protection control refers to multiple air compressors sharing a control cabinet, which controls multiple air compressors connected to the joint control cabinet and can be connected to the DCS operating system in the control room; The main content of joint control protection control includes setting and switching of the air compressor host, starting and stopping sequence and delay of single machine joint control, etc., to maintain the running time balance of each air compressor.

2. Explain the characteristics of the single machine controller for screw air compressors.

The single machine control device of screw air compressor is commonly used with IC board control panel or microcontroller control panel. The screw air compressor controller is an electronic product that controls the normal operation of the whole machine in the air compressor, and has functions such as automatic control, real-time monitoring, and fault handling of the unit.

The appearance of screw air compressor controllers varies from brand to brand, but their functions are similar.

Automatic control of the shutdown, standby, start-up, load, no-load, prolonged empty time, emergency shutdown and other states of the unit; Real time monitoring of multiple sets of data such as exhaust pressure and exhaust temperature to achieve automatic maintenance and protection functions of the unit; The use time of the three filters of the air compressor can be set. When the running time exceeds the corresponding set time, the indicator light will turn on to remind that the components need to be replaced; It can be upgraded and expanded through software, and flexibly applied in different industrial and mining situations; Easy to operate and master.

3. Introduction to the control functions of the air compressor control cabinet.

(1) In the joint control state, press the start button of any air compressor unit. After 2 seconds, this unit will start running. After 20 seconds, one unit will start until all units are running. If the pipeline pressure has reached the predetermined low limit, the units that have not been started will no longer be started.

(2) After the pressure reaches the high limit on the official website, the control cabinet issues an unloading command and automatically stops the standby machine after a 5-minute delay; If it is still in the unloading state, the auxiliary machine will automatically stop after a delay of 10 minutes; If the uninstallation signal continues to exist, the last host will automatically stop after a delay of 20 minutes.

(3) The data that can be input and modified includes the upper and lower limits of the compressed air main pressure setting, the conversion time of the main engine, the interval time between restarting the air compressor after shutdown, the startup delay of the main engine, auxiliary engine, and backup engine, and the shutdown delay of the main engine, auxiliary engine, and backup engine. When the pipeline pressure is lower than the lower limit set value, a loading signal is sent out, and the auxiliary machine automatically starts running after a delay of 20 seconds. If the pipeline pressure is still below the set value, the backup machine will automatically start running after a delay of 20 seconds.

(4) After any unit malfunctions, it will automatically switch out of the joint control state, while the other units will still automatically start and stop according to the pre-set program control requirements to meet the pressure requirements of the pipeline network, and emit fault sounds and light signals.

(5) It will automatically time the running time of each unit and automatically switch the host to achieve balanced running time of each unit.

(6) According to the requirements of the system, each air compressor can be switched out of the joint control state at will.

(7) It has the function of transmitting signals to the central control room, such as operation signals, long empty vehicle signals, heavy fault signals, light fault signals, alarm signals, signals for accepting permission to start from the central control room, host status signals, air compressor power status signals, and all operations and displays are on the operation panel.

4. What are the precautions for the single control and joint control conversion operation of the air compressor control cabinet?

(1) On the electrical control board of each air compressor, turn the selection switch to the joint control cut-off state, and the unit has separately exited the joint control state. Process operations can be performed separately on the air compressor operation panel of each unit.

(2) On the electrical control board of each air compressor, turn the single control joint control selection switch to the single control state, and then individual operations of each unit can be performed on the joint control cabinet panel.

(3) On the electrical control board of each air compressor, turn the selection switch to the joint control mode. On the operation panel of the joint control cabinet, turn the single control joint control selection switch to the joint control mode to perform joint control operations on the joint control cabinet panel.

(4) When switching from single control state to joint control state, the original states of each unit remain unchanged. Then, the start button on the control panel of the control cabinet must be pressed to enter the control mode.

(5) In the joint control state, when a serious fault occurs in the air compressor, the program automatically switches the machine out of the joint control state and the air compressor stops automatically. Subsequently, turn the control knob on the electrical control board of the air compressor to the cut out position. Cut off the power supply separately for maintenance. After the maintenance is completed, if the power is turned on and the control knob is turned to the cut in position, the unit can still automatically enter the control mode.