Differential Pressure Transmitter

The differential pressure (DP) transmitter is one of the most versatile instruments in process measurement. By measuring the pressure difference between two points, a single DP transmitter can calculate flow across an orifice plate, venturi or averaging pitot tube, determine liquid level in closed or pressurised vessels, or monitor the condition of filters, strainers and heat exchangers. Hamoon supplies DP transmitters from leading global manufacturers, with high static-pressure ratings, built-in square-root extraction and excellent long-term stability.

Units can be supplied with three- or five-valve manifolds, capillary-connected diaphragm seals for level service, and wetted parts in SS316L, Hastelloy C-276 or tantalum. HART is standard, with Foundation Fieldbus and PROFIBUS PA available, together with ATEX/IECEx flameproof and intrinsically safe certifications.

Typical applications

• Flow measurement of gas, steam and liquids with orifice plates and venturis
• Level measurement in pressurised vessels, boiler drums and separators
• Filter, strainer and heat-exchanger differential pressure monitoring
• Interface and density measurement with remote seals

Share your process conditions with Hamoon engineers to receive a complete technical selection, including primary element, manifold and accessories, and request a quote.

Key points when selecting a Differential Pressure Transmitter

• State the maximum static line pressure (MWP) separately from the measured differential.
• For flow, specify square-root extraction and a range matched to the primary element (orifice, venturi, pitot).
• Use remote diaphragm seals with capillaries for hot, viscous or corrosive media.
• Order a three- or five-valve manifold for easy isolation and calibration.

Differential Pressure Transmitter — frequently asked questions

Where are differential pressure transmitters used?

The most common uses are flow measurement with orifices and venturis, level in pressurised vessels and pressure-drop monitoring across filters, heat exchangers and compressors.

Can a DP transmitter measure tank level?

Yes. Level is calculated from the hydrostatic head and the fluid density; on pressurised tanks the low side is connected to the vapour space.