How many levels are there for low-voltage cable voltage?

Low voltage cables are classified according to voltage level

1. Low-voltage cable: suitable for power transmission and distribution lines fixedly laid at 50Hz AC and rated voltage 3kv or below.

2. Medium and low voltage cables: (generally refer to 35KV and below): polyvinyl chloride insulated cable, polyethylene insulated cable, cross-linked polyethylene insulated cable, etc.

3. High-voltage cable: (usually 110KV or above): polyethylene cable and cross-linked polyethylene insulated cable, etc.

4. Ultra-high voltage cable: (275~800 kV).

5. Ultra-high voltage cable: (1000 kV and above).

Extended information:

Notes on low voltage cables:

1. The buried depth of the direct buried cable should not be less than 0.7m. It should be wavy when laying. The small bending radius should not be less than the provisions in the "Code for Construction and Acceptance of Cable Lines for Electrical Device Installation Engineering" (gb50168-1992). The polychloride insulated power cable is 10 times the outer diameter.

2. The upper and lower parts of the direct buried cable should be laid with soft soil or sand layers not less than 100mm thick.

3. When laying the pipeline, the ratio of the inner diameter of the cable pipe to the cable shall not be less than 1.5.

4. Three-phase or single-phase AC single-core cables shall not penetrate into the steel conduit.

5. Metal cable brackets and cable conduits must be grounded (pe) or zeroed (pen) reliable.

6. When laying cables in the trench, the principle of low voltage and high voltage should be followed.

Low voltage cable