The definition of pf_active/coil/resistance should be more explicit

[MireilleSchneider]

Right now the definition of pf_active/coil/resistance is 'coil resistance' which is not exactly a definition. We would need e.g. to specify that this is the resistance at operating temperature and not at room temperature.

[imbeauf]

Well, we can of course add "at operating temperature" to the definition, on the other hand, it's a bit strange to imagine that someone would put a value there corresponding to a different temperature from the actual coil temperature.
I you are thinking of the use case of recording the resistance for different temperature values, e.g. for a pure machine description dataset, we could think of two options:

1. Having a top temperature_reference node like in the WALL IDS "Reference temperature for which the machine description data is given in this IDS"
2. Having a tabulated resistance vector as a function of coil temperature, for each coil. This would be an addition and wouldn't remove the current resistance node