Pressure transmitters are essential devices commonly used in to measure, monitor and regulate pressure variation in gases, liquids and fluids. They can play a crucial role in ensuring the safety, efficiency, and reliability of processes across multiple industrial sectors. Understanding of what is the output of a pressure transmitter is necessary for technicians and operators who rely on precise pressure readings in their work.
A pressure transmitter typically converts signal received from integrated pressure sensor into larger electrical signal who is subsequently transmitted to a control system(PLC/DCS) for real-time monitoring and regulation. Specifically, common types of signal output are as followed:
Current Output: The major prevalent output type is the current signal, typically in the form of a 4-20 mA current loop. The output has a linear relationship with pressure value which increases proportionally with pressure reading. For instance, the measuring range of (0~10)bar could designate zero point as 4mA while a pressure of 10bar corresponds to 20mA forming a linear graph over the span. This range allows for easy interpretation of pressure value and is widely used in industrial applications due to its robustness against electrical noise.
Digital Output: Intelligent pressure transmitters can provide a digital output in forms of smart communication such as HART, Modbus-RTU or other protocols. Digital outputs bring advantages such as higher precision, on-site modification and diagnosis, additional information transmitted to PLS/DCS, s and reduced susceptibility to noise. These smart digital outputs increasingly popular in modern automation systems.
Voltage Output: Some pressure transmitters can provide a voltage output, typically in the span of 0-5V or 0-10V. Voltage output type is less common than the current loop but can be especially useful in applications where voltage signals are preferred for control systems.
Frequency Output: Frequency output refers to converting pressure readings into a frequency signal. Although frequency signal is less commonly used in pressure transmitters because of higher cost and technical complexity, It can be rather beneficial in specific applications where high-speed data transmission is required.
After selecting the appropriate output signal, attention shall also be paid to some factors that may influence the output in practice:
Calibration: Proper calibration is a necessity for accurate pressure readings. Factory calibration must be performed to ensure the output corresponds to the actual measuring pressure in a proper way through comparing the transmitter’s output to a known pressure standard and adjusting it when necessary.
Temperature Effects: Temperature could have impact on output precision. Factory temperature compensation could help correct undesired temperature effect around ambience, but extreme temperatures can still affect performance of transmitter. It is crucial to select a transmitter rated for the specific operating temperature range.
Vibration and Shock: Vibrations and shocks would occur in some sections among industrial environments that can lead to unstable readings and damage to the instrument. It’s important to choose a robust vibration resistant structure design and apply necessary vibration damping measures to protect instrument integrity.
Medium Properties: The nature of the measuring medium can also influence the output. Factors like viscosity, corrosion, vary in states of matter and presence of suspended particles might lead to deviated pressure reading. Selecting correct type of transmitter compatible with specific properties of specific measuring fluid is essential for proper instrument functioning.
Forms of signal output from a pressure transmitter is a critical aspect of its functionality. As experienced instrument manufacturer in process control sector for over 20 years, Shanghai Wangyuan provides proven and reliable instruments of measurement with a wealth of experience on all kinds of output signals from common 4~20mA and smart communications to customized output. If you have any question or requirement on transmitter outputs don’t hesitate to contact us .
Post time: Dec-12-2024