- Jun 22, 2020-
1. When installing wires and cables in parallel with heating pipes, keep a distance of 2m, and keep 0.5m when they cross.
2. When the wires and cables are installed in parallel or across other pipes, a distance of 0.5m must be maintained.
3. When installing wires and cables directly, the depth of 1-35kV cables should not be less than 0.7m.
4. When the cables of 10kV and below are installed in parallel, the mutual clear distance is not less than 0.1m, the 10-35kV is not less than 0.25m, and the distance when crossing is not less than 0.5m.
5. The minimum bending radius of the cable must not be less than 15D for multi-core cables and 20D for single-core cables (D is the outer diameter of the cable).
6. 6kV and above cable connector
(1) When installing wire and cable terminal heads, the semi-conductive shielding layer must be stripped off, and the insulation must not be damaged during operation. Knife marks and unevenness should be avoided. If necessary, use sandpaper to smooth; the shielding end should be flat and Remove the graphite layer (carbon particles).
(2) The copper shield and steel armor of the plastic insulated cable end must be well grounded. This principle should also be followed for short circuits to avoid induced electrical dynamics at the steel armor end during unbalanced operation of three-phase, even "fire" and burning Sheath and other accidents. The grounding lead wire should be connected with tinned braided copper and cable copper tape. Soldering iron should not be used for sealing and welding with torches to avoid burning insulation.
(3) The three-phase copper shield should be connected to the ground wire separately. Note that the shield ground wire and the steel armor ground wire should be led out separately and insulated from each other. The position of the welding ground wire should be as low as possible.
7. The basic requirements for cable end and intermediate joint:
(1) The conductor is well connected.
(2) Reliable insulation, it is recommended to use radiation cross-linked heat shrinkable silicone rubber insulation material.
(3) Good sealing.
(4) Sufficient mechanical strength can adapt to various operating conditions.
8. The cable end must be waterproof and corroded by other corrosive materials to prevent breakdown due to aging of the insulation layer caused by water trees.
9. Cranes and forklifts must be used for loading and unloading of wires and cables. Horizontal transportation and flat laying are forbidden. When installing large cables, cable cars must be used to prevent the cables from being damaged by external forces or scratching the sheath and insulation due to manual dragging. The cable is not installed in the reel, and it is strictly forbidden to use manual hand to make the conductor bend and damage the insulation layer to cause a short circuit.
10. If wires and cables cannot be laid in time for some reason, they should be stored in a dry place to prevent sun exposure and water ingress into the cable ends.
11. The strong and weak currents of wires and cables cannot be managed together, but for the convenience of construction, some cable construction teams directly store all the wires together. The power cables, network cables, shielded cables, and frequency conversion cables are all placed in the same trunking. There will be strong interference between them, which will cause the signal to be unstable.