Application of Differential Pressure Switch in Backwash Filter

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Generally, it is suitable to use the adjustable set point type differential pressure switch in the automatic backwash filter, but for the sake of reliability, some manufacturers set the differential pressure set points at 50kPa, or 70-100kpa.

In general, the differential pressure switch uses the differential pressure of two pipes to send out electric switch signals. When the differential pressure of two ends in the series of liquid pipes rises (or falls), exceeds the set value of the differential pressure controller, it sends out switch signals to control the reversing valve or monitor the lubrication system. Then the valve will be opened (or closed) to reduce the pressure difference between the two ends of the system liquid pipe, so as to achieve the normal operation of the  backwash filter system.

The differential pressure switch with adjustable set point is installed at both ends of the filter. When the filter is dirty or blocked, the differential pressure at both ends exceeds the set value, and the differential pressure switch automatically sends a switch signal to alarm the user to clean the filter.

GE-511 Adjustable Differential Pressure Switches with Brass Body

For the automatic backwash filter, the signal of too high differential pressure is provided to the control system. When the differential pressure is greater than the set value, the brush motor starts to rotate to remove the impurities on the filter screen, open the blowdown valve to discharge the impurities. After a period of operation, the impurities and differential pressure decrease. When the differential pressure drops to the set value, the backwash is stopped.

GE-511 series Brass or stainless steel differential pressure Controller is Pressure Differential Switch with adjustable setpoint. The adjustable differential pressure switch could be calibrated directly by manufacturer according to customer's requirement, and printed the calibrated value on the label of product, so user needs not readjust in the field. The customer could calibrate by professional instrument according to the differential pressure required by equipment