when erecting electric wires what should be paid attention to
Cable laying is a technical activity. There are too many precautions and details in the process of cable laying. Before cable laying, check the insulation of the cable, pay attention to the winding direction of the cable when erecting the cable trays, and do a good job of cable preheating during cable laying in winter.
Precautions for cable laying
1. The insulation of cables shall be checked before cable laying. 2500V megger shall be used for 6~10KV cables, and the telemetering insulation resistance shall be ≥ 100M Ω; 1000V megger shall be used for cables of 3KV and below to measure the insulation resistance ≥ 50M Ω. Cables with doubtful insulation shall be subject to withstand voltage test and can only be laid after they are confirmed to be qualified.
2. When erecting the cable tray, pay attention to the winding direction of the cable. When pulling the cable, the cable shall be led out from the top of the cable reel to prevent the cable from loosening when the cable reel rotates. The cables sent out shall be held by people or placed on the rolling frame, and the cables shall not be rubbed on the ground or wooden frame.
3. During cable laying, its bending shall not be less than its minimum allowable bending radius. At the bend, the person pulling the cable shall stand in the opposite direction of the resultant force on the cable.
4. High voltage cables, low voltage cables and control cables shall be arranged separately, from top to bottom, from high voltage to low voltage, and control cables shall be arranged at the lowest layer. The cables shall be arranged at the bottom or inside of the cross as far as possible to make the exposed parts orderly.
5. During cable laying, spare length can be reserved near the cable terminals and cable joints, and a small margin shall be reserved for the total length of directly buried cables, which shall be laid in wave (snake) shape.
6. After the cable is laid, the signboards shall be hung in time. The signboards shall be hung at both ends of the cable, at the intersection, at the turning point and at the point of entering and exiting the building.
7. The cable becomes hard in winter, and the cable insulation is vulnerable to damage during laying. Therefore, if the temperature of the cable storage site is lower than 0~5 ° C before laying, the cable shall be preheated.
Editor’s summary: the above precautions for wire erection have been introduced here, and I hope it will be helpful to you. Because there is no support point for indoor stringing, the cable tray or cable ladder will be used for stringing. Note that the two are different and must be distinguished. If you want to know more about it, please follow.