How Do Cable Length and Lead Wires Affect PRT Accuracy?

Cable length and lead wire design significantly impact PRT measurement accuracy, especially in industrial installations where sensors are located far from control systems. Long cables introduce electrical resistance that can distort the PRT's resistance signal, leading to temperature errors if not properly compensated. Standard 2-wire PRTs are susceptible to lead wire resistance errors, making them unsuitable for long cable runs. 3-wire and 4-wire PRT configurations eliminate or reduce these errors by balancing cable resistance or providing separate sensing and excitation paths. 4-wire designs offer the highest accuracy and are preferred for precision applications and long-distance installations. Cable quality also affects performance; shielded cables reduce electrical interference from motors, drives, and high-voltage lines, preventing signal noise and unstable readings. High-quality, low-resistance cables maintain signal integrity over hundreds of meters. Proper installation, including avoiding cable runs alongside power lines, further reduces interference. Understanding how lead wires and cable length affect accuracy allows users to select the correct PRT configuration and wiring setup. With proper design, PRTs maintain full accuracy even in large industrial facilities with extensive cable runs.