Transmitters

What are Pressure Transmitters?

A pressure transmitter is an instrument that outputs an electrical signal based on a pressure measurement of a fluid (liquid or gas). Pressure transmitters are often used to monitor pressure of equipment in the process industry (tanks, pipelines, etc.).

Components of a Pressure Transmitter

There are two components of a pressure transmitter. The transducer, measures or senses the pressure, and converts the physical variable to an electrical signal. The transmitter magnifies and relays the signal for long distances to a PLC. The signal is representative of the pressure range from the transducer.

Pressure Measurement

Transmitters can measure pressure in three different ways:

• Gauge Pressure - pressure is compared relative to local atmospheric pressure
• Absolute Pressure - pressure is compared relative to absolute (zero) pressure
• Differential Pressure - the difference of pressure between two points

Advantages

• Measure pressure levels and pressure differences
• Made of piezoelectric materials
• Some pressure transmitters are self-calibrating

Disadvantages

• Expensive

References

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