ETAP Cable Calculated Impedance

[Nina~]

Hello Sir. Is there a reason why when I set protective conductor in 4/C cable, the impedance calculation cannot be perform ? It only work when i set it to neutral.

Also the No.of Conductor of the neutral is only one condutor. When I try to use 4*1/C cable and increase the No. of conductor of the neutral up to 4 conductor, the impedance cannot be calculate. I am using IEC standard. Does IEC standard only consider one neutral conductor as a return path ?

Thank you.

 

[7anoter4]

I am not a ETAP user but, if it is to follow IEC standard -let's say, for instance, IEC 60364-1- and you consider TN-S earthing system, the fourth conductor is for earthing and then the impedance of neutral it is actually the phase-to-earthing impedance. If it is only for neutral used and it is earthed only one end-usually the supply end-that means you have another earthing conveying way, not through this cable. However, you may use, in a way, for both neutral and earth as per TN-C-S system.
If you have an outside means for earthing it is not cable theory the address.
By the way, it will be easier if your cable presents 5 conductors-3 for lives 1 for neutral and 1 for earthing.