Pressure Transmitter

1. Definition and Function A pressure transmitter is an instrument that converts physical pressure parameters (from gases or liquids) into electrical signals such as current, voltage, or digital outputs. These signals are transmitted to secondary instruments, including indicators, alarms, recorders, or controllers, for monitoring and process regulation. Accurate range selection is one of the most […]

1. Introduction In process industries such as chemical, petrochemical, and power generation, flow measurement is a critical parameter for process optimization, cost control, and safety assurance.Among various flow meters, differential pressure (DP) flow transmitters hold more than 60% of the market share due to their simple structure, strong adaptability, and wide applicability. However, the accuracy

Pressure sensors play a critical role in industrial applications. In real operating environments, their performance can be affected by multiple interference factors, and in severe cases, the sensor may even be damaged. Therefore, quality testing is essential. The evaluation can be divided into two major aspects: interference immunity and measurement accuracy. 1. Interference Immunity Tests

1) Concept & Scope Interface level means the height of the boundary between two immiscible liquids of different densities (e.g., oil–water). A dual-flange remote-seal differential pressure transmitter infers the interface height from the pressure difference created by the two liquids across the measurement span. Typical uses: separators, coalescers, desalters, and oil–water interface tanks. 2) Media

1. Executive Summary A differential-pressure (DP) flow loop on a process line suddenly reported PV=0 and lost local display. The instrumentation team followed a “electrical chain first, then process side” approach. Measurements isolated the fault to a non-standard cable splice ~4–5 m upstream of the transmitter that had oxidized and opened the loop. After corrective

Differential pressure (DP) transmitters are the workhorses behind level, flow, and filter monitoring across process plants. Yet most performance problems trace back to fundamentals—mounting, impulse line routing, wiring, and commissioning. This guide distills field-proven practices so your DP devices start accurate and stay reliable. 1) How a DP Transmitter Works (Quick refresher) A DP transmitter

Reliable gauge calibration isn’t just about applying a reference pressure and writing down numbers. Accuracy class, pressure media, contamination control, elevation head, leak checks, mounting position, how you generate pressure, pre-cycling, gas thermodynamics, and even wrench torque all matter. Get these right and your results will actually reflect reality. 1) Know the Accuracy Class (and

1. Introduction In demanding industrial environments—characterized by high temperature, high pressure, strong corrosiveness, or crystallizing media—diaphragm-sealed pressure transmitters act as a critical safety and accuracy barrier. However, many users face performance failures due to subtle but crucial configuration issues, such as: Fill fluid solidifying in cold climates; Excessive capillary length causing slow response; Improper selection

1. Evolution of Regulatory Classification 1.1 Early Classification (1981–2016) The earliest relevant regulation dates back to the Safety Supervision Regulation for Pressure Vessels (Labour and Boiler Regulation No. 7 [1981]).Article 80 explicitly classified pressure gauges alongside safety valves as “safety accessories”, requiring periodic verification at least once a year. This classification placed pressure gauges in

1. Introduction Pressure gauges are not universal instruments. Selecting the wrong type for a specific medium can result in corrosion, explosion hazards, or measurement failure. This document explains the selection requirements for pressure gauges used in acetylene, ammonia, oxygen, and hydrogen sulfide-containing media, referencing SH/T 3005-2016 and related international standards. 2. Applicable Standards SH/T 3005-2016