The terminal sleeve is designed for installation on three-core cables with plastic or oil-impregnated paper insulation. It reliably protects cable power lines from moisture, moisture, solar radiation, conductive dust, chemically aggressive substances and environments, from a variety of negative atmospheric effects.
Unlike the connecting one, the end coupling is used only outdoors. Today, there is a huge variety of models of such devices, the use of which depends mainly on the design of the cable, its characteristics and operating conditions. For example, terminated heat-shrinkable sleeves KNTP are designed for cables with AC voltage up to ten kW. Such devices have high tightness, good mechanical and thermal strength, and have low cost.
For installation on cable lines with voltages up to one kW, the end coupler of the PKNTp-1kV model is used. Devices of this design are characterized by excellent thermal insulation properties and resistance to ultraviolet radiation. The end coupling, depending on its purpose, may have a steel, aluminum or cast-iron housing.
Separated cable cores are insulated with tubes made of a material resistant to adverse environmental influences. The cutting root is equipped with a hot-melt cone-shaped filler, which serves to level the electric field, it is insulated with a special glove.
When installing this product, lugs equipped with contact detachable screws are installed on the conductors of the power cable. Tips are carefully insulated, and their connection to the grounding conductor is done by soldering. In order to protect the root from a split, a special expansion insulator is installed on it. Depending on the cable design, the end coupling is equipped with phase insulators based on a pair for each core.
Structurally, the cable end coupling consists of a body, gloves with hot-melt adhesive applied to its surface, heat-shrinkable tubes for insulation of cable cores and cuffs. Also, the device’s delivery set includes fittings designed to connect the grounding wire, and lugs with stall type bolt heads.
Before starting installation, the dimensions of the coupling are carefully checked. Particular attention should be paid to the location of the external insulating heads relative to the front surface of the housing. Installation technology depends to a large extent on this. The location of the heads should correspond to the contacts of the connected cable. After this check, an oil seal is removed from the sleeve housing, the necessary slot is selected in it, the diameter of which corresponds to the thickness of the input cable.
Pipes are inserted into the openings of the housing, which are then pushed onto the cable cores. The extreme cores are carefully bent, then inserted into the corresponding slots of the housing. The housing itself should be promoted so that the middle core exits from it approximately 280 mm apart. Further, in full accordance with the requirements of the technology specified in the accompanying technical documentation of the product, it is necessary to proceed with the assembly of contact heads and extreme insulators on the case. And finally, the ferrules are connected to the contact tires of the insulator heads, after which they are securely fixed with bolts.