Instrumentation

1. Common Electrical Instruments 1.1 Multimeter Purpose: Used to measure DC/AC voltage, current, resistance, and in advanced models, capacitance, inductance, and power. Main Components: Indicator section: moving-coil meter (meter head). Measuring circuits: shunt, divider, rectifier. Switching device: selects measurement type and range. Usage Guidelines: Correctly connect test leads (red to “+”, black to “–”). Select […]

Abstract Thermal automation instruments and chemical automation instruments both belong to the broader category of industrial automation instruments, serving as key enablers for process monitoring and control. While they share a common foundation in principles, functions, and architecture, they also exhibit distinct differences due to variations in process media, application scenarios, and control objectives. This

Introduction In industrial equipment management, Preventive Maintenance (PM) and Predictive Maintenance (PdM) are two commonly adopted strategies. While the two terms differ by only a single word, they represent fundamentally different approaches to equipment reliability. This article compares their definitions, advantages, limitations, and suitable applications, helping enterprises choose the right maintenance strategy—or a combination of

Introduction In an instrumentation and control engineering project, the project documentation package is one of the core deliverables. It records all required documents throughout the entire lifecycle—design, procurement, installation, commissioning, and handover. A well-structured document set not only guides project execution but also ensures quality, safety, and regulatory compliance. 1. Design Documentation Design documents provide

Introduction In industrial automation and process control, the Modbus protocol is one of the most widely used communication standards. At the heart of Modbus lies the concept of the coil, a fundamental data type that plays a crucial role in device control and monitoring. This article explains what coils are, how they work, and why

1. Introduction A Remote Terminal Unit (RTU) is a key device in industrial automation and remote monitoring systems. It converts physical signals into digital data and transmits them to the central control system. Within the RTU architecture, Input/Output (I/O) modules act as the critical bridge between field devices and the control center, enabling both data

1. Explosion-Proof Requirements All electronic instruments installed in hazardous areas shall comply with IEC 60079 or GB 3836 standards, and must be certified with valid national explosion-proof certificates. 1.1 Zone 0: Use intrinsically safe instruments (EEx i) with isolation-type safety barriers. 1.2 Zone 1 & Zone 2: Explosion-proof type (EEx d) shall be the first

1. Functional Positioning Throttling Orifice Plate: Core component of differential-pressure flow measurement systems. Works with differential pressure transmitters and pressure taps. Its primary function is to generate a pressure drop across the orifice, establishing a quantitative flow–pressure relationship (ISO 5167 standard). Suitable for accurate measurement of single-phase fluids (liquid, gas, steam). Restriction Orifice Plate: Flow/pressure

1. Explosion-Proof Selection of Field Instruments All electronic instruments installed in hazardous areas shall meet the explosion-proof requirements of the designated zone and comply with IEC 60079 or GB 3836 standards, and shall hold valid national explosion-proof certificates. 1.1 Zone 0Instruments shall be intrinsically safe type (Ex i) and connected through isolated safety barriers. 1.2

1. Instrument Selection and Installation Standards 1.1 Matching Process Conditions Select instrument materials based on medium characteristics such as temperature, pressure, and corrosiveness (e.g., 316L stainless steel, PTFE lining). In explosive environments, use explosion-proof instruments certified by ATEX/IECEx. 1.2 Installation Guidelines Avoid strong electromagnetic interference: keep away from motors and variable-frequency drives; route signal cables