Instrumentation

In industrial instrumentation, theoretical knowledge is just like a wrench in your toolbox — it may not seem important at first glance, but when troubleshooting, it becomes indispensable. Whether preparing for certification exams or improving practical fieldwork, mastering instrumentation theory helps build a solid foundation. This document highlights several core concepts that often cause confusion […]

Introduction In industrial automation, RS-485 communication has become one of the most widely used methods for data exchange between devices. Thanks to its reliability, strong noise immunity, and long-distance capability, it is commonly found in factory automation, building control, and energy monitoring systems. However, RS-485 is not a single wiring method. It can be implemented

1. Introduction Steam temperature is one of the most critical parameters in thermal power plant operation. Compared with drum water level control, which has evolved into the classical three-element control system, steam temperature regulation remains highly complex. Multiple disturbance factors—ranging from load fluctuations to flue gas conditions and desuperheating water flow—can influence the dynamic behavior

1. Introduction The purpose of this document is to establish standardized requirements for the operation, inspection, maintenance, and overhaul of the Safety Instrumented System (SIS).The SIS is defined as an instrumentation system used to execute one or more Safety Instrumented Functions (SIF). It consists of sensors (e.g., switches, transmitters), logic solvers (controllers), and final control

This guide explains how to choose the installation height for combustible or toxic gas detectors based on whether the leaking gas is heavier or lighter than air. It also includes a special note for oxygen (O₂) sensors. 1) Classify the gas by buoyancy (relative to air) Let N = (gas molecular weight) / 29, where

To ensure the safety and reliability of instrumentation and control systems during seismic events, the following measures shall be adopted: 1. Anchoring of Instrument Equipment Instrumentation equipment such as control cabinets, auxiliary cabinets, instrument panels, instrument boxes, junction boxes, and field instruments shall be firmly fixed to floors or ground using foundations and supports.This prevents

Environmental sustainability and occupational safety are inseparable elements of modern process industries. Instrumentation plays a critical role in monitoring hazardous substances, controlling emissions, and ensuring compliance with environmental regulations. The following guidelines summarize best practices for instrumentation in environmentally sensitive applications. 1. Combustible and Toxic Gas Detection 1.1 Fixed Gas Detection In locations where combustible

1. Introduction Instrumentation in chemical plants serves as the core of process control, safety monitoring, and quality assurance. The acceptance of instrumentation installation directly affects the stability, safety, and accuracy of subsequent operations.Acceptance must strictly follow the “Code for Construction and Quality Acceptance of Automation Instrumentation Engineering” (GB 50093-2013) and special chemical industry regulations (e.g.,

Introduction In high-risk sectors such as chemical, petrochemical, and gas industries, the Safety Instrumented System (SIS) is the final layer of protection. However, design flaws, poor maintenance, and misuse of bypass functions can render this defense ineffective. This document provides a standardized, lifecycle-based SIS inspection checklist, covering design, installation, operation, maintenance, assessment, and documentation. It

1. Introduction Process instrumentation in the chemical industry relies heavily on signal transmission and power supply methods. The wiring configuration of transmitters and sensors—whether two-wire, three-wire, or four-wire—directly affects installation complexity, cost, measurement accuracy, and reliability. This article explains the principles, advantages, limitations, and typical applications of each wiring system, providing a comparative overview for