Article on cable jointing

Cable jointing kits instruction manual | How to joint cables using cable jointing kits for 11 kV (E) / 6.6 kV (UE) XLPE cable

Important note :- Before starting the installation please go through the installation instructions carefully. Stretch the self amalgamating insulating and semiconductor tapes to 70% of their width  and apply half overlapped.

Cautions :- 

1. Do not nick/ cut XLPE insulation while removing the semiconducting layer.
2. While wrapping F.S.D. pad no air avoids should be entrapped.
3. Keep gap between the conductors before crimping the ferrules.
4. Use correct size ferrules and crimping tool.
5. Keep the site and cable clean.

Cable Preparation Table :-

Cable size in sq.mm	L2	L0	LA	LI
3C X 16/25/35	775	20	60	20
3C X 50/70/95	800	20	60	20
3C X 120/150/185	840	30	70	20
3C X 225/240/300	880	30	70	20
3C X 400	900	30	70	20

Legend :- 

• L2 - Length of cable inside the mould
• L0 - Length of outer sheath
• LA - Length of armour
• LI - Length of inner sheath

Steps for joining the 11 kV cable | steps for cable jointing :

Step I :

• Place the cable so that they overlap by at least 150 mm as shown in below figure 1. Mark the center line of the overlap and then from the center line mark a distance L2/2 as in figure 1.

                                  

Step II :

• Prepare the cable by maintaining the length of armour and inner sheath as per the dimension given in the above table for the particular size of the cable as shown in below figure 2. 

Step III :

• Now unwind the metallic shielding from cores up to distance 110 mm plus half the ferrule length as shown in figure and cut off maintaining the remaining metallic shielding on the core tightly secured by Cu. binding wire as shown in below figure 3.

Step IV :

• Remove the core insulation for a length of half the ferrule length  +10 mm by using nylon string. Mark the distance of 80 mm with Tinned Cu. binding wire and remove the extruded semi-conducting layer without damaging the XLPE insulation of core as shown in figure. Smooth the XLPE insulation surface by means of Aloxite tape provided along with kit and clean the surface with a piece of mopping cloth soaked in core cleaning solvent. Also, the sharp cut edges of the semi-conducting layer should be grounded with the help of Al. oxide tape. Figure 3.

Step V :

• Crimp the Al. Inline ferrules as per normal practice and remove the burrs and wipe the Al. Online ferrules with a clean piece of mopping cloth soaked in core cleaning solvent. Fill up the space between Al. Inline ferrule, core insulation and crimped portion with HV Self Amalgamating semiconducting tape wrapping. Measure a distance of 20 mm from both sides of the wrapped semi-conducting tape apply stress grading pad of 30 mm width overlapping 10 mm of HV Self Amalgamating semiconducting tape as shown in below figure 4.

Step VI :

• Maintaining a gap of 5 mm from the semiconducting layer of core-wrap HV Self Amalgamating insulating tape so that the earlier noted dia. (of semiconducting tape) is increase by 10 mm as shown in figure 5.
• The gap of 5 mm maintained between the wrapped HV self amalgamating insulating tape and semi-conducting layer is filled up by a stress grading pad of 30 mm width as shown in figure. Apply HV Self Amalgamating semi-conducting tape each half overlapped about 10 mm over lapping on one side of metallic shielding to the other end of metallic shielding as shown in figure 5.

Step VII :

• Wrap two layers of HV self Amalgamating insulating tape on the HV Self Amalgamating semiconducting tape and then wrap the entire core with Tinned Cu. wire mesh from one end of metallic shielding to the other end as shown in figure 6 and above wrap it with PVC(NA) tape.

Step VIII :

• After completing all cores, connect the metallic shielding of each core to armour by Tinned Cu. binding wire. Place the Al. back ring and fix the Jubilee clamp on armour and connect the Tinned Cu. Braided earth continuity connection as shown in figure 7 Also place the core spacer between the core as shown in figure 7.

Step IX :

• Wrap foam tape around the cable where the mould has to be fitted and then cut the cable entry portion of the mould to suit the outer diameter of the cable and above the foam tape. Place the lower half of the mould in position and check the clearance between each core  and the mould and  then place the top half of the mould in position and check clearance again. Also ensure that the two halves of mould meet easily all along the flanges. If not, the cable entry portion has to be slightly enlarged. Apply mould adhesive on the flanges of mould clip holding and the cable entry portion is sealed with Black mastic sealing tape as shown in figure 8.
• Place support at center portion of mould with bricks. Open the resin container and stir its contents gently but thoroughly. Open hardener  container and pour its contents in resin string the compound slowly with the help of stress but thoroughly while adding to obtain  a uniform mixture for 5 minutes. Then pour the mixed compound into the  mould till it is filled up completely as shown in figure 8.

Contents in Kit :

1. Cable jointing compound (Resin Part)
2. Cable jointing compound (Hardener Part)
3. Stress Grading Pad (120 mm x 120 mm)
4. H.I.P. mould in two halves
5. Mould Adhesive
6. Core cleaning solvent
7. Core spacers
8. HV Self amalgamating insulating Tape
9. HV Self Amalgamating Semiconducting tape
10. Foam Tape
11. Tinned Cu. Flat braid for earth continuity connection
12. Tinned Cu. binding (short) for Cu. Tape screen
13. Tinned Cu. binding wire (18SWG)
14. Tinned Cu. wire mesh 
15. PVC (NA) Tape
16. Black Mastic sealing tape
17. PVC (A) tape (R, Y, B)
18. Nylon string for cutting the XLPE insulation
19. Aloxite tape (120, 150, 220)
20. Stirrer for Mixing compound
21. GPFC epoxy putty
22. Cleaning tissue (6 ml)
23. Mopping cloth
24. Al. backing ring
25. Jubilee clamp
26. Al. inline ferrule (compression tape)
27. Mould holding clips
28. Identification tag
29. Packing list
30. Instruction sheet