Assembled RTDs are industrial temperature sensors designed for measuring and controlling the temperature of liquids, steam, gases, and solid surfaces, typically within –200 °C to 600 °C. They are commonly used with indicators, recorders, and electronic controllers, and are categorized into Pt100 platinum and Cu50 copper types—Pt100 offered in Class A (±0.06 Ω) or Class B (±0.12 Ω), while Cu50 has a nominal resistance of 50 ± 0.05 Ω. Featuring a spring-loaded sensing element with imported thin-film resistors, they deliver high anti-vibration performance, stable accuracy, and reliable pressure resistance, with insulation resistance >100 MΩ at room temperature. Sheath materials include GH3030 and 1Cr18Ni9Ti alloys, and installation options include fixed threads or flanges; proper selection requires specifying the type code, accuracy class, and insertion depth, based on the principle that metal resistance varies with temperature to produce a corresponding output signal.