Describe a typical calibration procedure for a differential pressure transducer.

• A. Connect to known pressure references; record output at multiple points; determine offset, span, and linearity; apply temperature compensation; generate calibration table/transfer function.
• B. Calibrate by adjusting offset only.
• C. Use random pressures and interpolate.
• D. Use a single-point calibration only.

Answer: (C)

Calibrating a differential pressure transducer means mapping its electrical output to actual differential pressure across the full operating range, and doing so in a way that accounts for zero offset, sensitivity (span), nonlinearity, and temperature effects. The typical procedure applies known differential pressures at multiple points across the range using calibrated pressure references, then records the transducer’s output at each point. From these data you determine the zero offset (output when pressure is zero), the span (change in output per unit pressure), and any nonlinear behavior by fitting a transfer function or calibration curve. Temperature compensation is often included because output can drift with temperature, so measurements at representative temperatures or a compensation model are incorporated. The result is a calibration table or transfer function that accurately converts the transducer’s output to differential pressure for normal operation.

This approach is preferred because relying on a single point or arbitrary pressures won’t reveal the true slope, possible nonlinearity, or temperature drift, leading to error across the range. Using multiple known pressures and incorporating temperature effects yields a robust, reliable calibration, whereas methods that adjust only offset, use random pressures, or rely on a single-point calibration fall short in accuracy and consistency.