Precious metal thermocouple wire Type S, also known as Platinum-Rhodium 10-Platinum thermocouple wire, is a high-precision temperature sensing element composed of two precious metal conductors. The positive leg (RP) is a platinum-rhodium alloy containing 10% rhodium and 90% platinum, while the negative leg (RN) is pure platinum. It offers exceptional accuracy and stability in high-temperature environments, making it the preferred choice for precise temperature measurement in metallurgy, ceramics, and high-temperature industrial furnaces.​

Standard Designations​

• Thermocouple Type: S-type (Platinum-Rhodium 10-Platinum)​

• IEC Standard: IEC 60584-1​

• ASTM Standard: ASTM E230​

• Color Coding: Positive leg – green; Negative leg – white (per IEC standards)​

Key Features​

• Wide Temperature Range: Long-term use at up to 1300°C; short-term use up to 1600°C​

• High Accuracy: Class 1 accuracy with a tolerance of ±1.5°C or ±0.25% of reading (whichever is larger)​

• Excellent Stability: Less than 0.1% drift in thermoelectric potential after 1000 hours at 1000°C​

• Good Oxidation Resistance: Stable performance in oxidizing and inert atmospheres​

• Low Thermoelectric Potential: Generates 6.458 mV at 1000°C (reference junction at 0°C)​

Technical Specifications​

​

Chemical Composition (Typical, %)​

​

Product Specifications​

​

Typical Applications​

• High-temperature sintering furnaces in powder metallurgy​

• Glass manufacturing and forming processes​

• Ceramic kilns and heat treatment equipment​

• Vacuum furnaces and crystal growth systems​

• Metallurgical smelting and refining processes​

We also provide S-type thermocouple assemblies, connectors, and extension wires. Free samples and detailed technical datasheets are available upon request. For critical applications, we offer additional certification of material purity and thermoelectric performance.