Identifying the Rated Voltage of Power Cables

The cable voltage rating is defined as the value of three frequency voltages expressed in kV.
The design voltage rating between any one core and the metal sheath or "ground".
For multi-core cables, the design voltage rating between any two cores, and for single-core cables, the system design voltage rating.
The rated voltage of the cable is expressed as a combination of the maximum value of the system voltage and the highest system voltage used for the equipment.
It is used to design the insulation thickness of the cable, and the high voltage test conditions, and to determine the maximum AC or DC operating voltage of the cable.

With social development, Electrical applies so many ways, so it plays an important role in our life, we need to keep it safe and have a long work life. 

Now pls see the analysis below:

Cable high-voltage and low-voltage method of distinction:

Check the Normal Cross-Section.

The innermost of the cable is a conductivity core (copper or aluminum), followed by outward: insulation, semiconducting layer, shielding layer, filling layer, PVC inner sheath, armor layer, and PVC outer sheath.

Check the Insulation Thickness

(1) Low voltage (1kv below) 1 ~ 3mm thick, 10kv cable 5 ~ 8mm, 35kv cable 10mm; low voltage or weak cable generally a layer of insulation and protective layer.

(2) After the high-voltage cable to remove the skin insulation, is wrapped in the cable core, the white plastic is like the main insulation, low voltage cable without the main insulation, but the rubber protective layer.

Check the Voltage Register

Cables according to different voltage levels are habitually divided into:

Low voltage cable: 300/500V -0.6 / 1kV;

Medium voltage cable: 3-35kV;

High-voltage cable: 35-110kv;

Extra High-voltage cable: 110-750kV.