Difference between low voltage cable and medium voltage cable

There are many kinds of AAAC Cables. According to voltage, they can be divided into low-voltage cable, medium voltage cable and high-voltage cable. What we can often touch and use in our life are low-voltage cable and medium voltage cable. How can we distinguish them? Some people say it’s 1kV, others say it’s 10kV. How to distinguish between low voltage cable and medium voltage cable? Now let Dr. Bao popularize science for you.
1、 Voltage level
According to different voltage levels, cables are habitually divided into low voltage power cables (3KV and below), medium voltage power cables (6kV ~ 35kV), high voltage power cables (66kV ~ 220kV) and ultra-high voltage power cables (above 220kV).
2、 Application and laying
Low voltage cable
Low voltage cables are used to transmit and distribute electric energy, mainly used in urban underground power grid, outgoing lines of power stations, internal power consumption of industrial and mining enterprises, and power transmission under river and sea water; It has the characteristics of reliable operation, no pole, no occupation of the ground, no hindrance to the view, less external influence and so on. The common laying methods include direct buried laying, AAC Cable trench laying, tunnel laying and wall laying.


■ medium voltage cable
MV cables are mostly produced as part of power generation and distribution networks for many applications such as utilities, petrochemicals, transportation, wastewater treatment, food processing, commercial and industrial markets. The common laying methods are underground direct buried laying; Laying of protective pipe (steel pipe, plastic pipe, row pipe, etc.); Laying of cable structures (cable trench, tunnel or working shaft, etc.); Laying in other public facilities (public facilities such as roads, railway bridges, tunnels or underground shopping malls, wharves, trestle roads, etc.); Underwater laying, etc.
3、 Observe the appearance
■ insulating materials
Low voltage power cable insulation material can be: PVC, cross-linked polyethylene;
Medium voltage power cable insulation material: cross linked polyethylene.
■ number of cable cores
The number of low-voltage power cable core is divided into: 1, 2, 3, 4, 5 core, 3 + 1 core, 3 + 2 core, 4 + 1 core
The number of medium voltage power cable core is divided into: 1 core, 3 core (so this kind of cable is mainly used for trunk transmission, 3-phase balance).
Minimum specification
The minimum specification of low voltage power cable is 1.5mm ²;
Minimum specification of medium voltage power cable: 3.6/6kv: 10mm ², 6/6kV, 6/10kV:16mm ², 8.7/10kV, 8.7/15kV:25mm ², 12/20kV:35mm ², 18/30kV:50mm ², 21/35 kV、26/35 kV: 50mm ²。
Color discrimination
Low voltage power cable cores are distinguished by different insulation colors, color lines or digital marks;
The core of medium voltage power cable shall be distinguished by ribbon.


Conductor structure
The conductor of low voltage power cable can be round non compact, round compact and irregular compact;
The conductor of medium voltage power cable must be round and tightly pressed( At present, the medium and low voltage power cables produced by our company all adopt circular compact structure
Basic structure of cable
The basic structure of low voltage power cable is conductor + insulation + filling + wrapping + outer sheath;
The basic structure of medium voltage power cable is conductor + three-layer coextrusion (conductor shielding, insulation, insulation shielding) + copper tape shielding + filling + wrapping + outer sheath.
Low voltage cable and medium voltage cable have different uses due to different voltage levels, composition, structure, etc. when choosing, you can choose according to your own actual situation.