Temperatures when simulating DC cable losses

[AhmadMick]

Hi and Wish you a pleasant day. I would like to ask about DC cable calculations:
+) How does PVSyst determine the temperature when calculating DC cable loss

+) What formula is used when calculating DC cable loss.

+) Is the temperature for DC cable loss and Temperature of the cell equals at all times during simulations.

Pardon my bad english, if my question is unclear please let me know. Thak you for your time.

[André Mermoud]

In PVsyst, the cables temperature is  fixed to 50°C at any time, supposed to be an "average" during all conditions of the simulation 

In the reality, the wire temperature is obviously not well defined: it depends on the wire mounting mode, the possible exposition to the sun, the current, etc... 

The sensitivity of the resistivity to the temperature is 0.39%/°C, for the copper as well as for the aluminium. 

See the help https://www.pvsyst.com/help/project-design/array-and-system-losses/ohmic-losses/metal-resistivity.html?h=resistivity

NB1: in a next version, it will be possible to choose the temperature for any part of the wiring. In the present time, you can modify it in the advanced parameters. 

NB2: the wires temperature has nothing to do with the cell's temperature in the module.