755LR-M0290

Frequently Asked Questions

How to Install 755/775LR Deadbreak Elbow Connectors

This guide provides step-by-step instructions for installing 755/775LR Deadbreak Elbow Connectors, ensuring fully shielded, submersible deadfront cable connections for 35kV class systems. All apparatus must be de-energized during installation, and this product should only be installed by competent personnel trained in high voltage electrical equipment safety practices.

Estimated time: 1h 30m

1. Position and Cut Cable

   Position the cable in its final assembled location, ensuring enough slack for elbow removal. If using concentric neutral cable, unwind the neutral wires. Cut the cable 1-3/4 inches (45mm) from the centerline of the mating product.

2. Clean Cable Outer Jacket

   Clean the outer jacket of the cable for a distance of 24 inches (610mm) from the cut end.

3. Prepare Cable Insulation and Shield

   Prepare the cable by removing the outer jacket (if applicable), semi-con shield, and cable insulation according to the specific cable type (e.g., jacketed, non-jacketed, unishield, lead sheath). Refer to the provided diagrams for precise dimensions, typically involving measurements like 10-3/8 inches, 11-3/8 inches, and 13-5/8 inches from the cable end for insulation, semi-con shield, and tape marker respectively. If using a grounding device or shield adapter, follow their specific instructions.

4. Bevel Insulation and Install Cable Adapter

   Bevel the end of the cable insulation at a 45-degree angle, approximately 1/4 inch (6mm) back. Thoroughly clean and lubricate the cable insulation, working towards the semi-con shield. Install the cable adapter, small end first, until it is flush with the edge of the tape marker.

5. Trim Insulation and Verify Conductor Length

   Carefully remove any cable insulation protruding beyond the end of the cable adapter, cutting it flush. Ensure you do not cut or nick the cable adapter or the conductor. Verify that the exposed conductor length is between 4-3/8 inches (111mm) and 4-3/4 inches (121mm); if not, re-do the assembly.

6. Install and Crimp Compression Lug

   For copper conductors, fully insert the conductor into the compression lug. For aluminum conductors, wire brush the conductor immediately before fully inserting it. Before crimping, measure the 'Check Dimension' (distance from lug end to cable adapter); it must be less than 7 inches (178mm). Crimp the lug according to its specific instructions. After crimping, wipe off any excess inhibitor. Verify the distance from the end of the compression lug to the cable adapter is between 6-7/8 inches (175mm) and 7-5/8 inches (194mm); if not, re-do the assembly.

7. Lubricate and Install Elbow

   Lubricate the cable adapter and the inside of the elbow's cable entrance. Push the elbow onto the cable adapter until it cannot advance further. Confirm the cable adapter remains flush with the tape marker; reposition if necessary. Finally, remove the tape marker.

8. Prepare Elbow and Mating Part

   Remove protective caps from both the elbow and the mating part. If the mating part lacks a stud, hand tighten the threaded stud (supplied with the elbow) into it. Thoroughly clean and lubricate both the elbow and the mating part with the provided lubricant, ensuring all surfaces remain clean. DANGER: DO NOT connect or disconnect mating products while energized, and DO NOT energize while disconnected.

9. Connect Elbow to Mating Part

   Carefully push the elbow onto the mating part, aligning the hole in the compression lug with the stud on the mating part.

10. Secure Opposite Mating Part (if applicable)

    If connecting another mating part to the opposite end of the elbow, clean and lubricate its surface. Insert this mating part into the elbow, engage the threads, and hand tighten. Torque the mating part to the specifications provided with its instructions.

11. Install Insulating Plug and Cap (if used)

    If an insulating plug is used as a mating part, clean and lubricate the inner surface of the voltage detection cap. Place the cap on the elbow and push down firmly until it snaps into place.

12. Ground Cable Shield

    Insert one end of a grounding wire (at least No. 14 AWG Copper equivalent) through the grounding eye and twist to form a small loop, taking care not to damage the eye. Connect this wire to ground using a suitable connector. Ensure the cable shield is properly grounded, either via a grounding device (following its instructions) or an alternate method. It is also recommended to waterproof the cable jacket at this point to prevent moisture ingress.

13. Perform Voltage Test and Re-cap

    Use the integral capacitance test point to determine if the circuit is energized. First, remove the test point cap with a hotstick, peeling it off at an angle. WARNING: This is a capacitance device, not directly connected to the conductor; use only a suitable sensing device designed for capacitive test points and follow its manufacturer's directions. Treat the elbow as energized until a 'no voltage' indication is confirmed by other means, as contamination or incorrect equipment can cause false readings. After testing, clean and lubricate the inside of the cap with silicone lubricant and replace it on the test point.

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