Power Cables Jointing Procedure (Steps Include)

Cable Jointing or joining is a crucial process in electrical installations, requiring careful attention to detail and follow to industry standards. Whether joining cables for power distribution, telecommunications, or industrial applications, following a systematic approach is essential to ensure safe and reliable connections. In this article, we’ll outline the step-by-step process for cable joining, including best practices and tips for success.

LV Power Cables Jointing Procedure.

The purpose of this is to describe in detailed procedure for cable jointing using Armored Type Raychem Jointing Kit and Junction Box, in which connection will be through terminal block. This procedure shall be communicated and understood by the personnel involved associated with the tasks before commencing the activity.

Materials, Tools and Equipment.

• Raychem LV Cable Joint Kit.
• Junction Box.
• Support Materials.
• Welding machine.
• Fire blanket.
• Fire extinguisher (Type A, B, C).
• Hand tools.
• Torch.
• Crimping Tool.
• Other miscellaneous materials.
• PPE.

For TELE-3 Power Cable.

• Verify the location of the cables to be jointed.
• Install the junction box at the convenient location without any obstruction from the cable tray.
• Ensure that cables to be jointed are line checked to ensure correct cables are being jointed.
• Cables to be properly glanded and spliced.
• Connect each core to the terminal block according to the termination schedule.
• Neatly arrange the cable inside after the completion of the termination.
• Properly close the Junction Box.
• Junction Box and armored cable to be properly grounded/ bonded accordingly.

Cable Jointing Steps.

General Instructions:

1. Cables to be jointed shall be first cleaned by a Cable Cleaner to wipe out the dirt or dust.
2. Check to ensure that the kit to be used fits the cable.
3. Refer to the kit label for detailed instruction.
4. Carefully read and the follow the steps of the installation instruction.
5. Ensure that cables to be jointed are line checked to ensure correct cables are being jointed.
6. Ensure to connect each same core color coding.
7. Use a propane (preferred) or butane gas torch.
8. Adjust the torch to obtain a soft blue flame with a yellow tip.
9. Pencil-like blue flame should be avoided.
10. Keep the torch aimed in the shrink direction to preheat the material.
11. Keep the flame moving continuously to avoid scorching the material.
12. Clean and degrease all parts that will come into contact with adhesive.
13. If solvent is used follow the manufacturer’s handling instructions.
14. Tubing should be cut smoothly with a sharp knife leaving no jagged edges.
15. Start shrinking the tubing at the position recommended in the instruction.
16. Ensure that the tubing is shrunk smoothly all around before continuing along the cable.
17. Tubing should be smooth and wrinkle free with inner components clearly defined.

Steps for Cable Joining Include.

1. Overlap the cables to be jointed by about 150 mm.
2. Mark the reference line (the middle of the overlap).
3. Slide the outer sleeve over one cable end.
4. Remove the over sheath and armor according to the dimensions given in Table 1.

  ILLUSTRATION A

• Lift the armor wires and slide at the support rings underneath.
• If necessary build up the bedding under the support ring with a piece of oversheath.
• Secure the ends of the armor wires with wire binder.
• Remove the bedding level with the end of the armor wires.
• Shape and position the cores as shown in Illustration A and cut them at the reference line.

Slide the insulating sleeves over the long core ends.

• Remove the insulation on all cores according to the dimension

I  =  half the connector length + 5 mm.

For maximum connector dimension see Table 2. Joint the conductors by crimping. Remove any sharp edges. Clean and degrease the connectors and the insulation.

• Center the insulating sleeves over the connectors. Shrink them into place starting at the center and working towards ends.

• Relay the cores as far as possible. For ease of installation hold them in place with few layers of PVC tape. Wrap the joint case round the joint and clamp the ends into the armor wires using screw clips.

• For conductors cross sections from 6-16 mm², fix the joint case in place with roll springs as shown in the picture.

• Cover the sharp edges of the screw clips with a piece of cable oversheath. Smooth out the area round the screw clip with filler.

• Clean and degrease the ends of the oversheath for length of about 150 mm. Position the outer sealing sleeve centrally over the joint area. Start shrinking in the center working towards the ends.

• Joint completed. Allow the joint to cool before applying any mechanical strain.