Loading…
Skip to main content

Instrumentation & Calibration

I/P 4–20 mA ↔ 3–15 psi

Check the conventional linear signal relationship of an electro-pneumatic current-to-pressure transducer during calibration, loop checks or troubleshooting.

Signal conversion

Nominal basis: 4 mA = 3 psi and 20 mA = 15 psi.

mA
psi

Field use

Check the electrical-to-pneumatic interface.

Useful when verifying a conventional I/P transducer between a DCS/PLC output and a pneumatic positioner or actuator interface.

Calculation basis

% = (mA − 4) / 16 × 100
psi = 3 + 12 × (% / 100)

This is the conventional linear 4–20 mA to 3–15 psi relationship used by standard I/P transducers. It does not evaluate supply-air quality, output capacity, hysteresis, zero/span adjustment or a manufacturer-specific alternate range.