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 ...
moreWhy has there been, for some time, a separation between the accuracy classes for "wire-wound resistance" and "film resistance" Pt100 measuring resistors?
In the past, no distinction had been made between the two basic types of measuring resistor and their temperature limits. Practice, however, showed that film resistors (thin-film/chipset resistors) have a (not insignificant) deviation form the char ...
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Why is there some white foaming inside the case of liquid-filled pressure gauges?
With liquid-filled pressure gauges, white foam can occasionally form inside the case. This is the well-known phenomenon of an electrochemical reaction between aluminium components (e.g. pointers, dial) and the case filling (mainly with glycerine-wa ...
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