Pressure Measurement – Engineering Fundamentals
Pressure measurement is one of the most fundamental field instrumentation skills. It forms the base for flow and level measurement and plays a major role in daily plant troubleshooting.
Types of Pressure
Many field errors come from misunderstanding pressure reference.
Learn more: Pressure Basics
Pressure Transmitters (PT / DP)
- Convert pressure into 4–20 mA signal
- Require proper impulse piping
- Installation errors cause most failures
- Scaling must match process design
The transmitter is rarely the root cause — installation usually is.
Common Pressure Field Problems
- Pressure drifting after shutdown
- Reading unstable during temperature change
- Mismatch between local gauge and DCS
- Impulse line blockage
- Manifold valve leakage
Root cause reference: Pressure Failures – RCA Guide
Pressure Troubleshooting Logic
- Verify process isolation
- Check impulse line slope and blockage
- Confirm manifold valve position
- Compare local gauge vs transmitter
- Review DCS scaling
Full decision tree: Pressure Troubleshooting – Master Guide