Need Advice on Cable for Service Voltage 20 kV

I'm getting more and more worried about the quality and integrity of electricians around the world. There should be somebody on site properly educated and authorized to read and decide from the IEC standard which type of cable you should use. If I said yes to either of these cables and they immediately burst into flames and took out your entire installation, will you blame me for the damages? If I said that neither are suitable for the installation, would you buy a more expensive cable on my word.

If you don't have this standard yourself and are looking for me to tell you what it says, I say buy the standard yourself.

I'm not even sure if the IEC standard is the appropriate standard for your location.

Is your system earthed or unearthed? if earthed, is it solid earthing or impedance earthing?

Dear electricalexpert65,

my system is Solid Grounding at low voltage side (transformer 11/20 kV)

thank you

If your LV Side (11kV) is solidly earthed, I assume that your 20kV side is unearthed. Ans that is the side for which you want to select a cable. If so, you have to select a 20kV (UE) Grade Cable.

Somewhat Vague Question:

"if my service voltage 20 kV, can i use 12/20 kV N2XSY cable or must 18/30 kV ?"

Somewhat Vague Answer:

http://www.ddacables.com/katalog/pdf/n2xsy6-10kv_12-20kv_18-30kv.pdf

It is also wise to look into other parameters and not just voltage ratings as usable life depends on many other parameters also. These specs can be found in standard cable type if specified.

yes, msamad

i also agree with you, but there is some time, my customer complain me with saying, cable 12/20(24) has voltage discharge 20.76 kV. so what about if i tap my transformer become 21 kV (5 %), will it reduce the age of cable faster ?