The selection of the tension clamp is mainly determined according to the different conditions of the power line conductor. There are two common situations.

1. Selection of line tension clamps when using LGJ and LJ conductors

When using LGJ or LJ wire, since the tension clamp is clamped on the outer diameter of the wire, the type of tension clamp used should be selected according to the outer diameter of the wire. For example, the LGJ-185/30 wire is used in the power line. It is calculated that its outer diameter is 18.88mm. From the above table, it is known that the tension clamp it should use is NLL-4, NLL-5 or NLD-4.

It should be noted here that the outer diameter of the LGJ wire is the outer diameter of the wire calculated from the section of the aluminum wire of 185mm and the section of the steel core of 30mm, not simply from the section of the aluminum wire of 185mm. LGJ wires of the same specification have different steel core cross-sections and wire outer diameters, so the tension clamps used for LGJ wires of the same specification are not necessarily the same. If it is an LJ wire, since it does not have a steel core, the outer diameter of the wire can be calculated by the section of the aluminum stranded wire.

In addition, since the tension clamp is clamped on the outer diameter of the wire, we require the outer layer of the LGJ or LJ wire to be covered with aluminum tape during construction to prevent damage to the wire during crimping.

2. Selection of line tension clamps when insulated conductors are used

Compared with bare wires, insulated wires have the advantages of high safety and reliability, reduced wire losses, and less wire corrosion. When using insulated wires, we need to pay attention to the fact that the tension clamp is clamped on the outer diameter of the "conductor", not the outer diameter of the "conductor", so it should be based on the outer diameter of the wire instead of the outer diameter of the "conductor". The outer diameter of the conductor is used to select the type of tension clamp used.

In addition, we should tighten the screws evenly when installing the tension clamp, and require that there is no increase in wire stress at the contact surface between the installed wire and the original metal, so as to prevent the wire from being damaged due to breeze vibration or other wire oscillations. Ensure that the gripping force of the tension clamp on the wire is not less than 95% of the breaking force of the wire.