Isotech 108462 copper point SPRT model

The Isotech Copper Point SPRT 108462 is a standard platinum resistance thermometer (SPRT), specially developed for measurements up to the Copper Point of 1084.62°C. This SPRT is a breakthrough in temperature metrology, as it enables measurements with higher accuracy compared to thermocouples in this temperature range.

Traditionally, thermocouples are used for temperatures above the silver point (961.78°C), but at the copper point, the sensitivity of a Type R thermocouple is limited to 14 µV/°C, making small temperature changes difficult to detect. The development of the 108462 SPRT now allows temperature changes at the copper freezing point to be determined with greater precision.

Innovative Design for Maximum Stability

The 108462 SPRT combines more than 30 years of Isotech expertise in silver point SPRTs with innovative technologies. The instrument contains a synthetic sapphire mandrel, which optimally supports and stabilises the platinum winding.

Because platinum is sensitive to atmospheric influences, Isotech has developed a solution in which the aluminium oxide (alumina) casing is filled with air and kept under slight pressure via a small air pump. This keeps the oxygen concentration around the winding constant, stabilising oxidation and maximising long-term stability. In addition, the four platinum wire connections are insulated with quartz glass and routed through four separate drill holes.

Technical Specifications

• > Measuring range: 0°C to 1100°C
• > Nominal resistance at 0°C (Ro): 0.25 Ω
• > Length: 650 mm
• > Diameter: 7.5 mm
• > Sheath material: Aluminium oxide (alumina)
• > Mandrel material: Synthetic sapphire
• > Cable: 2.5 metres
• > Ionisation: +9V DC bias for more stable measurements

Applications

The Isotech 108462 Copper Point SPRT is ideal for:

•  > Primary and secondary temperature calibration laboratories
• > Research into phase transitions of copper at 1084.62°C
• >Replacement of thermocouples in high-temperature calibration procedures
• > Ring comparisons and accreditation processes
• > Use in ITS-90 fixed-point cells for reference measurements

The Isotech Copper Point SPRT is a groundbreaking instrument that helps scientists and metrologists perform ultra-precise temperature measurements. Thanks to its patented design, this SPRT delivers unrivalled reliability and performance in high-temperature calibration applications.