Input Levels for Thermocouples and RTD Pt-100. And the ways it has to be used. Thermocouples are selected on the basis on how they are mounted or fixed, the environment, the temperature range that is measured and finally the price you can afford for a particular application. Sometimes mechanical wear or chemical environments may eat away the sensors, so a cost-effective solution has to be evolved.
One customer wanted a special Pt-PtRh very high temperature sensor for molten aluminum. It was very difficult and costly to even arrive at a solution. So a non-contact infra-red sensor may save lot of time-money and even reduce risk of injury.
| Temperature Deg C |
J type TC mV |
K Type TC mV |
T type TC mV |
RTD Pt-100 Ohms |
| -- 0200.0 | -05.891 | -05.603 | 018.49 | |
| -- 0100.0 | -03.553 | -03.378 | 060.25 | |
| -- 0050.0 | -01.889 | -01.819 | 080.31 | |
| 0000.0 | 00.000 | 00.000 | 00.000 | 100.00 |
| + 0050.0 | 02.585 | 02.022 | 02.035 | 119.40 |
| + 0100.0 | 05.268 | 04.095 | 04.277 | 138.50 |
| + 0200.0 | 10.777 | 08.137 | 09.286 | 175.84 |
| + 0300.0 | 16.325 | 12.207 | 14.860 | 212.02 |
| + 0400.0 | 21.846 | 16.395 | 247.04 | |
| + 0500.0 | 27.388 | 20.640 | ||
| + 0600.0 | 33.096 | 24.902 | ||
| + 0800.0 | 33.277 | |||
| + 1000.0 | 41.269 | |||
| + 1200.0 | 48.828 | |||
| Environment | Reducing | Oxidizing | High Moisture | General |
| Fe | Ni+Cr | Cu | Pt | |
| Alloy + Pos. | Iron | Chromel | Copper | |
| Alloy - Neg. | Constantan | Alumel | Constantan | |
| Cu+Ni | Ni+Al | Cu+Ni | ||
| Alpha | 0.00385 | |||
| + Positive | White | Yellow | Blue | White |
| - Negative | Red | Red | Red | Red |
| Reference | NIST | NIST | NIST | DIN 43 760 |
| Alloy | Fe-K | Cr-Al | Cu-K | PLATINUM |
| ANSI | J | K | T | Pt-100 |
For J, K, ∓ T Thermocouple Read "Temperature" + Room Temperature for mV shown applied to equipment, eg. If Room Temperature is 25 Deg C and mv applied is 10.777 for J Type STC1000 then reading should be 200 + RT = 225 deg C. The mV shown are for Reference Junction at 0 Deg C.
It would be better if you refer links below, The above table i made long ago, then a Scan with OCR later formatting. It could have errors.
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