CABLE TRANSITION JOINT
Cable network is a mixed infrastructure due to the use of cables of distinct types and modifications.
Cable heat shrink transition joint are intended for connection of cables with various technical characteristics: type of isolation, construction of cores, level of peak voltage in cable network. One of the main functional requirements for cable transition joint are versatility of cable mechanical connectors and insulating materials. Also, it is important to keep the oil-sopped composition inside the cable and prevent it from leaking.
Cable shrink transition joint by ZKA, Raychem, Radpol, Cellpack, Ensto, Sicame, 3M, IEC, ПЗЭМИ, КВТ, CABELNA ARMATURE LLC are used for different types of isolation of cable (PVC isolation, plastic isolation, mass-impregnated paper isolation), 3-core, 4-core or 5-core cables, easy in exploitation and resistance to mechanical effects.
CHARACTERISTICS OF CABLE TRANSITION JOINT
It is most effective to apply system of connection by a heat shrink method in combination with mastics and sealants for connection of cables of a different construction.
Cable heat shrink transition joint can be installed on cables and wires of different construction with different technical characteristics which to consider when choosing a transition joint:
- voltage in the cable network: 0,4 kV; 1 kV;
- number of cable cores: 3; 4; 5;
- type of dielectric cable insulation: polymeric (PVC) insulation; plastic insulation, mass- sopped paper insulation, rubber insulation;
- availability of armored or unarmored cable or screen.
Cable heat shrink transition joint is enclosed, and it supplies mechanical and electrical integrity of the cable network.
Sealing the connection, elimination of the formation of gas cavities is provided by sealants that prevent moisture and air from entering to the transition joint.
Heat shrink materials resistant to temperature, moisture, and UV rays, and in addition, they have oil-resistant properties.
Cable connectors are universal, and it is applied to group of sections of a cable with cooper or aluminum cores.
For convenience of installation of all accessories in joints by CABELNA ARMATURE LLC technologically agreed by the method of installation and geometric sizes. Heat shrink tubes are supplied with a glue, resistant to hot temperatures which significantly reduces the risk of damage to the cable burner during installation.
- transition joint to SIP up to 1 kV without armored: 3KNTPSIP 1, 4KNTPSIP 1
- transition joint to SIP up to 1 kV with armored: 3KNTPbSIP 1, 4KNTPbSIP 1
- transition joint from mass-sopped paper cables to polymeric cables: (3P+3B)STP 1, (4P+4B)STP 1, (3P+4B)STP 1, (4P+3B)STP 1
HOW TO CONNECT A POWER CABLE BY CABLE TRANSITION JOINT
The main stages of restoring the integrity of the cable by transition join is connecting cables of different constructions.
Mechanical and electrical strength of the contact connection in transition joint is provided by universal mechanical connectors with shear heads 4 bolts on each core with a locking membrane, which forms reliable contact at connection of cooper or aluminum cable with round or sector construction of cores.
The contact connection in transition joint has a high degree of corrosion protection. Contact bolts do not sit on a carving during all service period due to high technical characteristics of aluminum alloys of the EU countries.
Mechanical connectors with shear heads use 4 bolts when connecting cables with different constructions and are used by manufacturers: ZКА, Raychem, Radpol, Cellpack, Ensto, Sicame, 3M, IEC, CABELNA ARMATURE LLC.
Restoration of electrical and mechanical strength of insulation of cable at the joint is provided by heat shrinkable components supplied with a glue.
Cable heat shrink breakout is designed to seal the root when cutting the cable, and for inserting SIP lines (AsXSn) into tubes, pipes, or cable ducts. At branching of cores, the cable does not crack after installation and does not form microcracks. Together with sealant it creates a massive construction. It allows to carry out repeated regasification without risk of damage of the transition joint.
Insulating tube is resistant to temperature changes, restoring primary insulation of cables core.
Insulating connectors tube of the increased electric durability for isolation of a mechanical connector guarantees repeated protection against high voltage.
The resin ensures that the sealing of the connection, equalization of the electric field, and cutting the formation of gas cavities prevents moisture and air coming from outdoor inside of a joint.
INSULATION PARAMETERS OF CABLES AND WIRES OF DIFFERENT CONSTRUCTIONS
The main parameters of cable insulation are its electrical strength at breakdown voltage, heat resistance, frost resistance and mechanical strength of the heat shrink sheds at the flexibility radius of the cable.
Marks of cables whose construction includes PVC insulation are АВВГ, ВВГ, АВВГз, ВВГз, АПвВГ, ПвВГ, АВБбШв, ВБбШв, АВБВ, ВБВ, АВВБ, АВВБГ, ВВБГ, АПвБбШв, ПвБбШв, АПвБбШп, ПвБбШп, ВВбШв, NYM, N(A)YY, NAYBY, N2XY, AXMK, AMCMK, MCCMK, N2XH, N2XCH, NHXH, NHXCH, MCMK or their analogs.
Polymeric (PVC) insulation of cable is a common type of cable insulation, which is characterized by high electrical resistance. The advantages of PVC insulation are low cost, high resistance to chemicals, acids, humidity, low flammability, high allowable load current (compared to mass-sopped paper isolation higher by 30%), large flexibility radius, high storm-term thermal resistance. Disadvantages of PVC insulation are:
- under the influence of UV rays the aging process is activated,
- low flexibility at a temperature up to +70 ⁰С significantly reduces the insulation resistance,
- the lack of resistance of high temperatures.
Marks of cables whose construction includes mass-impregnated paper insulation: ААБ2л, ААБ2лШв, ААБ2лШп, ААБл, ААШв, ААШп, АСБ, АСБ2л, АСБ2лГ, АСБ2лШв, АСБВнг(А)-LS, АСБГ, АСБл, АСБлШв, АСБШв, АСГ, АСШв, СБ, СБ2л, СБ2лГ, СБ2лШв, СБВнг(А)-LS, СБГ, СБл, СБлШв, СБШв, СГ, СШв, ЦААБ2л, ЦААБв, ЦААБвГ, ЦААБл, ЦААБлГ, ЦААШв, ЦАСБ, ЦАСБ2л, ЦАСБВнг(А)-LS, ЦАСБГ, ЦАСБл, ЦАСБлШв, ЦАСБШв, ЦАСШв, ЦСБ, ЦСБ2л, ЦСБВнг(А)-LS, ЦСБГ, ЦСБл, ЦСБлШв, ЦСБШв, ЦСШв, N(A)KBA, N(A)KLEY or their analogs.
Mass-impregnated paper insulation of cable has a long service period, good electrical properties, and low cost. It is made of multilayer mass-sopped paper cable of high strength, which is based on sulfate cellulose, and sopped with a special tacky or non-flowing composition. This type of insulation is suitable for cables up to 35 kV. The metal cover protects against moisture penetration inside to cable, so this product can be used in a wet environment, and in the presence of additional protection under water. The advantages of this type of insulation are high electrical insulation properties.
Disadvantages are moisture absorption, high fire risk, low resistance to mechanical damage and fluidity of insulation at high temperatures. It is recommended to use the conductor only for horizontal laying.
Marks of cables whose construction includes plastic insulation of cables are: (А)ПвП, (А)ПвВ, (А)ПвБП, (А)ПвБВ, (А)ПвПу, (А)ПвПг, (А)ПвПуг, (А)ПвП2г, (А)ПвПу2г, АПвЭВ, ПвЭПу, АПвЭгаП, PVC, PE, XLPE, EPR, N(A)2XS(2)Y, N2XS(F)2Y, HXCMK, AHXAMK-W, RG7H1R, XnRUHKXS, XRUHAKXS, XRUHKXS, A2XS(F)2Y, 2XS(F)2Y, N(A)2XS(2)Y, N2XS(F)2Y, HXCMK, AHXAMK-W, RG7H1R or their analogs.
“Cross-linked polyethylene” (XLPE) is used for the manufacture of high-voltage cable products that are installed underground. The advantages of “Cross-linked polyethylene” (XLPE) cables are high throughput, resistance to mechanical damage, high flexibility, low hygroscopicity (moisture absorption), the ability to heat up to +130 °С, low dielectric loss, the ability to lay on complex routes.
Brands of cables, constructions of which includes XLPE insulation are: XLPE insulation of cables: СІП, СИП, ASXSn, NYM, СИП-1, СИП-2, СИП-4, СИП-5, СИПг, СИПн, СІП-1, СІП-2, СІП-4 (САПт), СІП-5.
Thermoplastic polyester (PET) insulation with high frost resistance has the non-polar dielectric polyethylene and is not prone to the formation of chemical and physical bonds, resistant to aggressive environments, and UV rays. The advantages of PET insulation are high tensile strength, high moisture resistance, resistance to chemicals, resistance to bending and abrasive effects, low reactive resistance.
Thermoplastic polyester (PET) insulation is characterized by high resistance to rainfalls, especially in winter, high fire resistance. Thermoplastic polyester (PET) insulation prevents the accumulation of snow and ice. It also became possible to install AsXSn on the facades of buildings, which was prohibited during the installation of ordinary wires.
Marks of cables whose construction includes rubber cables are; АВРБГ, АВРГ, АНРБ, АНРБГ, АНРГ, ВРБ, ВРБГ, ВРГ, НРБ, НРБГ, НРГ, H05RR-F, H05RN-F, H07RN-F, H07ZZ-F, H01N2-D, NSSHOU, NSGAFOU, NSHXAFO, H07RN8-F.
Rubber insulation is made of natural or artificial rubber, used when you need to increase cable flexibility or frost resistance. The advantages are:
- high flexibility combined with mechanical strength;
- the insulation is made for cables that are designed to power mobile current collectors, subject to repeated bending of cables;
- high hygroscopicity.
The disadvantages of rubber insulation are the rapid loss of elasticity under the influence of UV rays, which reduces the physical and mechanical properties of the cable, low operating temperature of the core (not more than + 65°С), sensitivity to chemical reagents.