Answer / greenborhan

I actually don't know why we multiply by 25, but for
your better knowing we don't get the correct cut result
by multiplying mV by 25, this procedure is only true for
k-type thermocouple. But for all other types of
thermocouple you have to follow the specific table for mV
and temperature.
greenborhan@gmail.vcom

Answer / carl_ellis

Apparently, your temperature signal is linear across a mV
range, coming from some type of temperature transmitter,
and the mV value represents temperature/25.

If your source is a raw thermocouple signal, then
multiplying by 25 does NOT result in a true temperature
value because
- cold junction compensation has not be applied
- thermocouples are not linear

Temperature transmitters perform both of those tasks, cold
junction compensation and linearization of the output
signal.

Carl Ellis
Measure First

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