Ask the Expert – Filter Status Switch

Differential Pressure Switch Series ADPS

Question: What setpoint should I set my differential pressure switch to for indicating when my filter is dirty?

Answer: Although Dwyer sells low-cost, low differential pressure switches with dual scale field adjustable setpoint knobs, such as our Series ADPS Differential Pressure Switch which is ideal for filter status monitoring, we are unable to advise what setpoint the switch should be set to. That information has to be obtained from the filter manufacturer. The filter manufacturer will be able to provide a recommended pressure drop across the filter when they recommend servicing or replacing the filter. All filters are different and have unique pressure drops and factory recommended service intervals, which is why the filter manufacturer needs to provide the recommended pressure drop across the filter or setpoint in the case of Dwyer Instruments ADPS.

Once you have a desired setpoint, installing and setting the ADPS can be done quickly and easily. It is compact and has external mounting tabs to make installation a breeze. Additionally, the conduit connection can be rotated for added convenience. Lastly, the dual scale field adjustable setpoint knob allows the  Series ADPS Differential Pressure Switch  to be set very quickly and without the use of a separate gauge, calibration pump, pneumatic tubing, and tees which is common among other low differential pressure switches that only have a blind screw adjustment for setting the setpoint.