Due to a manufacturing error, there is a fixed resistance value in the resistor’s thermocouple wire; how can this fixed resistance value be eliminated?
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The compensation wire is connected to the thermal resistor, resulting in an extra 90 ohms – what could be the reason?
You know it’s the wrong wire; are you still going to use it?
The wire is the wrong one; it must be replaced....
For three-wire thermistors, whether the wire resistance is 9 ohms or 91 ohms has little impact on the temperature reading. At 0°C, a wire resistance of 91 ohms will result in a reading that is about 0.2°C lower. At 200°C, a wire resistance of 91 ohms will cause the reading to be about 5°C lower
The problem with the three-wire system isn’t that serious, but it’s still recommended to replace it
Eliminating resistance can be achieved in a DCS, but this line resistance is non-linear; the key issue is that it’s not possible to use another approach
I replaced it with the transmitter cable that was nearby
Is the line resistance 91 ohms? Even the compensation wires shouldn’t be this large; it’s recommended to check the wiring. The three-wire system mentioned above is clearly unreliable! Since a compensation wire is being used, it can only be a two-wire system.
The key issue isn’t just the line resistance; there’s also a thermoelectric potential, so how can this be compensated for?