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 are the response times of the various measuring inserts?
The measurement of the response time is carried out in flowing water in accordance with DIN EN 60751 and VDI / VDE 3522.
- Ø 6 mm 1xTyp K, ungrounded: t0.5 = 3.3 sec. t0.9 = 7.9 sec.
- Ø 6 mm 1xTyp K, grounded: t0.5 = 1.1 sec. t0.9 = 3.5 sec.
- Ø 6 mm 1xPt1 ...
What does the designation "1/3 DIN" mean with resistance thermometers?
IMPORTANT: The terms 1/3 DIN, and also 1/5 DIN and 1/10 DIN, have NOT been STANDARDISED!
By May 2009, with the introduction of the new DIN EN 60751, there was no standardised accuracy class better than Class A. Some manufacturers of resistance therm ...
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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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