1. What Are The Advantages Of Cross-Linked Heat-Shrinkable Cable Accessories?
Answer: This is a new type of material, which has the advantages of superior electrical performance, small volume, small mass, easy installation, and matching materials compared with other kinds of accessories nowadays. In addition, cross-linked heat-shrinkable cable accessories are weather-resistant, dirt-resistant, and have flame retardant self-extinguishing capability.
2. What Are The Requirements For The Mechanical Strength Of The Cable Conductor Connection Points?
Answer: The mechanical strength of the connection point is generally lower than the tensile strength of the cable conductor itself. For fixed laying of power cables, the tensile strength of the connection point requires no less than 60% of the tensile strength of the conductor itself.
3. What Are The Main Properties Of The Insulation Layer Materials Of Power Cables?
Answer: Insulation layer materials of a wire and cable should have the following main properties;
- High breakdown strength
- Low dielectric loss
- A reasonably high insulation resistance
- Excellent discharge resistance
- A certain degree of flexibility and mechanical strength
- Stable insulation performance over time
4. When Laying Cables Mechanically, What Are The Provisions Of Traction Strength?
When dealing with copper core cable traction head, the allowable traction strength is 70N/cm. For aluminum-core cables traction head, the acceptable traction strength is 40N/cm. If you are using a wire mesh set traction, the acceptable power for a lead sheathed cable is 10N/cm, and for a pure lead sheathed cable is 40N/cm.
5. What Are The Provisions For A Cable Protection Tube?
Answer:
- The cable needs to be inside the protection tube when laying. The inner diameter of the tube should also not be less than 1.5 times the outer diameter of the cable. Elsewhere, the concrete pipe, terra cotta pipe, asbestos, cement pipe should not be less than 100mm inner diameter.
- The bending radius of the cable pipe shall be per the provisions of the bending radius of the cable penetrated.
- Each tube should not exceed a maximum of three elbows, and right-angle bends should not be more than two.
6. How To Measure The Outer Diameter Of The Cable Sheath?
Answer: Carry out measurements at five points evenly distributed around the outer circumference of the wire and cable sheath. After getting the measurements of each of the five points of the sheath’s outer diameter, calculate the average value using the five measures obtained. The average value is the outer diameter of the cable sheath.
7.How To Connect Copper-Core Cables Of Different Cross-Sections?
Answer: A different copper-core cable and wire cross-section can open a weak back copper receiver and then be connected using the tin welding method. Alternatively, you can use a pure copper rod to connect the copper receiver and connect the copper-core cables using the crimping technique.
8. Briefly Describe The Process Of 10KV Cross-Linked Cable Heat-Shrinkable Production Of The Indoor Terminal Head?
Answer:
- Preparation stage: check whether the heat-shrinkable cable accessories are available and whether the models match. Also, check and confirm that the cable has no moisture.
- Excise the excess cable and decide on the cable length according to the site conditions.
- Strip the sheathing.
- Weld the earthing wire to the steel strip.
- Fill trig port and wrap around sealant.
- Install the three-core branch sheath, sheathing into the root and shrinking from the middle, first towards the root and then towards the fingers.
- First, strip copper tape and outer semi-conductive layer. Then, strip and cut copper tape over 20mm from the mouth of the three-core branch sheath. It would be best if you were careful to avoid damage to the primary insulation of the wire and cable and remove the clean semi-conductive layer.
- Install the stress pipe, the pipe mouth, and the end part of the branch sleeve butt after heat shrinkage.
- Install terminal blocks.
- Install the insulating tube.
- Install the sealing tube.
- Installation of phase colour pipe after verification
9. What Are The Installation Steps For Indoor And Outdoor Prefabricated Terminals?
Answer:
- Position the cable at the intended location, fix it, clean the surface, and strip the outer sheath in line with the instructions. If there is a particular need, the length of the outer sheath can be adjusted. Lead-out two groups of earth wires from the copper tape and outer sheath armour,
- Measure the required size of the wire and cable upwards from the outer sheath mouth and remove the excess wire. After that, put in the heat-shrinkable three-finger sleeve to the root of the three-fold mouth by the middle heating shrinkage. Measure the required size upwards from the finger sleeve upper mouth (350~380mm for 35kv). Remove the excess copper tape (retain 20mm), then keep the predetermined semiconductor location and crimp out the line terminal seal
10. The Application Of Wire And Cable Is Divided Into Three Main Categories. Which Categories Are These?
The power system
The power system uses wire and cable products. The wires used are mainly overhead cable, electrical cable, solar cable, teflon wire, battery cable, high-temperature wire, trailer wire, and electrical wire and cable for power equipment.
The information transmission system
Wires and cables used for information transmission systems are municipal telephone cables, television cables, electronic cables, radio frequency cables, fiber optic cables, data cables, electromagnetic lines, power communications cables, or other composite cables.
The machinery and equipment, instrumentation systems
In this part of the bare wire, almost all other products are used in addition to the overhead cable. However, the main cables used are power cables, electromagnetic wire, data cables, and instrumentation cables.
