Filter monitoring, pump inlet/outlet measurement and air-duct measurement operate under different conditions. The same differential pressure value does not make instruments interchangeable. Specify line pressure and medium as well as the differential range.

Define the measurement task

Is the required result a switching alarm, a continuous analogue measurement, or both? Local display, separate measuring channels and communications affect the selection. Describe the measurement location and the signal expected by the control system.

Separate range from static pressure

A small differential can exist on a high-pressure line. Verify differential range, allowable static line pressure and one-sided overpressure limits separately. Full-scale range alone is not a sufficient selection criterion.

Installation and process conditions

Medium compatibility, temperature, vibration, orientation and impulse-line layout affect the measurement. Define manifold, isolation and venting requirements for the application. Follow the manufacturer’s identification of high- and low-pressure connections.

Commissioning and quotation review

Confirm code, connection size, output and supply, then record scaling and alarm setpoints. In a quotation request, separate normal operating values from maximum values to avoid ambiguity. Qualified personnel should perform installation and functional checks using the manufacturer’s instructions.

Manufacturer product information