What is a sensor?
A sensor is a device that detects a physical condition or change in its environment and converts it into a signal that can be measured,
A sensor is a device that detects a physical condition or change in its environment and converts it into a signal that can be measured,
If you work with P&IDs (piping and instrumentation diagrams), you’ve probably seen instrument bubbles marked PT, PIT, or PDT and wondered what they mean. The important thing to know is this: on a P&ID, the “pressure transmitter symbol” usually does not show what the physical instrument looks like. Instead, it shows what the instrument does and how it fits into the process or control loop. In this guide, we’ll explain what a pressure transmitter symbol represents, how to read tags like
A pressure transmitter works by converting the physical pressure of a gas or liquid into a standardized electrical signal (most commonly 4–20 mA, often with HART or MODBUS on top). In most industrial designs, the process pressure deflects a metal diaphragm, that force is transferred to a sensor element (often piezoresistive), and onboard electronics linearize, temperature-compensate, and scale the signal to the chosen output. What a pressure transmitter is doing in one sentence Pressure → diaphragm movement → sensor changes electrically → electronics correct + scale → output signal. That’s the core principle whether you’re measuring gauge pressure,
A differential pressure (DP) level transmitter measures liquid level by sensing the pressure at the bottom of a vessel and subtracting the pressure at the
Pressure transmitter accuracy describes the maximum expected deviation between the pressure value the transmitter reports and the true process pressure, usually expressed as a percentage
A high-temperature pressure transmitter is a pressure sensor built to read hot media (typically ~120–150 °C) while protecting its electronics and accuracy; in Pondus Instruments’
To calibrate a pressure transmitter: isolate it from the process, vent and equalize pressure, apply the lower-range pressure (LRV) and set zero, apply the upper-range
A differential pressure (DP) transmitter is an instrument that measures the difference between two pressures (high side “+” and low side “–”) and converts that
A flow transmitter measures how much fluid is moving through a pipe by sensing a pressure-based signal—most commonly the differential pressure (ΔP) created by a
Core principle At the heart of most industrial transmitters is a piezoresistive bridge bonded to a diaphragm system. Process pressure acts on a thin metal