The coefficient 0.00385 is defined and enforced by the IEC 60751 international standard, making it the universally accepted specification for modern industrial platinum RTDs. It comes with a globally unified resistance-temperature conversion table, standardized calibration procedures and full compatibility with nearly all data acquisition modules, temperature controllers, transmitters, PLC systems and DCS platforms. Whether matching imported high-end equipment or domestic industrial devices, products with α=0.00385 achieve seamless interchangeability, stable signal conversion and consistent measurement output across the world. It supports full-scenario application, convenient maintenance and unified system integration, laying the foundation for standardized temperature measurement worldwide.
In contrast, the coefficient 0.00392 has a slightly higher resistance change rate per degree Celsius. It was widely used in early domestic industrial instruments and some legacy European and American testing equipment, but has gradually been phased out due to poor universality. RTDs with α=0.00392 lack a unified global supporting ecosystem, with limited compatible transmitters, acquisition cards and calibration instruments. Their interchangeability is extremely poor, and they can only be matched with dedicated old equipment, which greatly limits flexibility in system upgrading, replacement and expansion.
Today, more than 99% of the global industrial market adopts the α=0.00385 standard. The 0.00392 coefficient is only retained in a small number of obsolete legacy systems for maintenance purposes, and is no longer used in new projects, automated upgrades or international cooperation programs. One of the most serious risks in sensor selection is ignoring the temperature coefficient parameter. Mismatched coefficients will lead to fixed and continuous temperature deviations, which cannot be corrected by conventional calibration. In severe cases, such deviations can cause abnormal process control, product quality defects, equipment damage and even production safety accidents.
For all new design, procurement and system renovation projects, I strongly recommend giving priority to platinum RTDs with α=0.00385. Before confirming orders, engineers must verify the temperature coefficient index in product specifications to ensure complete consistency with on-site equipment and control systems. Adhering to the IEC standard coefficient is the most reliable way to maintain measurement accuracy, system compatibility and long-term operational stability, which is also the core consensus of the global precision temperature measurement industry.
