The application of power products has a minor impact on social security, and the better safe use of power fittings has become an issue that we cannot ignore.
In densely populated areas with numerous trees and high pollution, we are increasingly using insulated wires instead of bare wires. It has the advantages of high safety and reliability, reduced line loss, and less wire corrosion compared to bare wires. When using insulated wires, we need to pay attention to the fact that the strain clamp is clamped on the outer diameter of the "wire" instead of the "conductor", so the type of strain clamp used should be selected based on the outer diameter of the wire rather than the outer diameter of the conductor. For example, in the power line, JKLGYJ-150/8 steel core reinforced cross-linked polyethylene insulated overhead cable is used. After calculation, it is found that its conductor outer diameter is 15.30mm, plus its insulation skin thickness of 3.4mm and conductor shielding thickness of 0.5mm. It is known that its conductor outer diameter is 23.1mm. According to the table above, the strain clamp that should be used for it is NLL-5. If we choose the equipment clamp based on the conductor outer diameter of 15.30mm at this time, the selected equipment clamp may not be usable.
In addition, when installing tension clamps, we need to tighten the screws evenly. It is required that there is no increase in wire stress at the contact surface between the installed wire and the metal, in order to prevent wire damage caused by light wind vibration or other wire oscillations, and ensure that the grip force of the tension clamp on the wire is not less than 95% of the wire's tensile strength.