Thermometer in cryogenic design - Innovative design for low-temperature measurements
Applications
- Extremely-low temperature measurements
- Applications with liquid hydrogen (LH2)
- Cryogenic tanks
- Cryogenic pipelines
- Hydrogen liquefaction plants
Special features
- Innovative design with high accuracy
- Usable with all relevant thermometers
- Approved for applications in hazardous areas
Description
Due to the global use of hydrogen, extremely low-temperature measurement during transport and storage is gaining an ever-greater relevance. With the cryo design, WIKA provides a suitable option for all relevant temperature measuring instruments for this demanding application.
In laboratory trials, resistance thermometers (Pt1000) and thermocouples (type E) were tested for their suitability in cryogenic applications. The special design of the cryogenic thermometer features a high accuracy of ±3 Kelvin at -253 °C [-423 °F] as well as high reproducibility.
The test data from laboratory investigations served as the basis for calculating new polynomials for Pt1000 resistance thermometers in the range of -258 ... -200 °C [-432 ... -328 °F] which are used in the configuration of WIKA transmitters.
What effect does poor insulation resistance have?
In accordance with DIN EN 60751 section 6.3.1 the insulation resistance between each measuring circuit and the sheath, at a minimum test voltage of 100 V DC, must not be less than 100 MOhm.
Should the insulation resistance be too low, a measuring er ...
moreHow thick is the wall thickness of an MI cable?
Most manufacturers give a minimum wall thickness which corresponds to 10 % of the external diameter of the MI cable.