¿Is it posible to extend QUAD probes?

From Spain we are asked about the possibility of extending the temperature probes of the QUAD and, if so, how much. The answer is that the temperature probes can be extended up to 30 meters. Nevertheless, we have to take into account a series of technical aspects:

Zennio temperature probes are thermistors, that is to say, its electric resistance varies depending on the temperature. Moreover, these thermistors are NTC-type so their resistance decreases when the temperature increases.

That is the reason why, when the probes are extended with wire, the ohmnic value of the resistance that the set presents is different from the value presented by the probe when it is alone, and it will depend on the type of wire used to extend.  Therefore, it is possible that an error margin appeared in the temperature measure and in order to reduce as much as possible this error, it is recommended:

1) Use wire with the most similar section to the probe (never smaller).

2) Carry out a good connection (use wire clamps if possible).

Once done, we can introduce a calibration for the temperature sensor, when configuring the QUAD parameters, in order to correct the error introduced by the wire extension that we have used. For that, we recommend to carry out temperature measures before and after adding the wire to the probe. And finally, program the calibration offset according to the difference between the measures for correcting the error.

NOTE: The error is noticeable for considerable wire lengths.