DIRECT ANSWER
What is the practical starting point?
Select a pressure transmitter by measurement reference, required range and performance, overpressure and transient exposure, process medium, temperature, wetted materials, connection, installation and electrical interface. Range alone does not define a safe or suitable configuration.
SELECTION FACTORS
Data to confirm before model selection
Use this list to prepare a traceable quotation request.
- 01Define whether the task requires gauge, absolute or differential pressure.
- 02Record minimum, normal and maximum pressure, possible vacuum, static pressure and transient or overpressure conditions.
- 03State the medium, composition, concentration, solids, viscosity and process-temperature cycle.
- 04Check every wetted material, seal, gasket and process connection for the service.
- 05Decide whether a direct connection, impulse line or manufacturer-designed diaphragm-seal system is appropriate.
- 06Define required uncertainty, stability, response and calibrated range without using turndown as a substitute for pressure rating.
- 07Match power, output, communication, enclosure and hazardous-area evidence to the control system and destination.
TECHNOLOGY COMPARISON
Compare the decision factors
| Decision | Use when | Verify before selection |
|---|---|---|
| Gauge pressure | The process pressure is referenced to local atmosphere | Atmospheric reference behavior, range, vacuum and overpressure |
| Absolute pressure | A stable vacuum reference is required | Absolute range, process connection and temperature effects |
| Differential pressure | The difference between two pressure points is the measured variable | Static pressure on both sides, orientation, impulse or seal arrangement |
| Direct process connection | The sensing diaphragm and connection are compatible and accessible | Wetted materials, plugging, temperature and mounting |
| Diaphragm-seal system | Corrosive, viscous, plugging, sanitary or temperature service needs isolation | Seal material, fill fluid, diaphragm, capillary, elevation, response and temperature effect |
FAQ
Questions engineers ask first
Last reviewed:
What is the difference between gauge and absolute pressure?
Gauge pressure is referenced to atmosphere; absolute pressure is referenced to vacuum. The process and reporting requirement determine which reference is correct.
Can a high turndown ratio solve every pressure range?
No. Calibrated span must still be evaluated with required uncertainty, stability, process noise and response, while overpressure and static-pressure ratings are separate limits.
When should a diaphragm seal be considered?
It may be appropriate for corrosive, viscous, plugging, hygienic or temperature service, but the transmitter and filled seal assembly must be selected and evaluated as one system.
ENGINEERING SUPPORT
Turn process data into a reviewable instrument request.
Share the medium, operating envelope, installation and required output. We will flag missing information before confirming a model.