Mike Dolt Enterprises
Mike Dolt Enterprises
User: NEEngineer, Location: Southeastern PA
Asked on: Saturday, March 26, 2011 at 6:15 pm EDT
Answered on: Tuesday, May 14, 2024 at 3:20 am EDT
Question: I will be running EMT from a bus duct switch with THHN wire to a 6 x 6 junction box. I then plan to drop bus cable with a 60 amp female plug. The machine will have a bus cable with a 60 amp male plug . This will be a 480v three phase drop. My question is how is the best way to terminate in the junction box between the thhn and the bus drop cable. I haven't used a lot of bus drop cable. Any comments would be greatly appreciated.
Materials
THHN wire (appropriate gauge for 480V, 60A) 6 x 6 junction box Bus drop cable with 60A female plug Bus drop cable with 60A male plug Wire nuts or crimp connectors Insulated butt connectors Electrical tape
Termination Procedure
Step 1: Prepare the THHN Wire Cut the THHN wires to the appropriate length. Strip the insulation back approximately 1-1/2 inches. Form pigtails by twisting the strands from each wire together.
Step 2: Prepare the Bus Drop Cable Cut the bus drop cable to the appropriate length. Remove the outer jacket from both ends of the cable. Identify the ground, line 1 (L1), line 2 (L2), and line 3 (L3) terminals on the male and female plugs.
Step 3: Connect the THHN Wire to the Junction Box Connect the ground wire from the THHN cable to the grounding screw in the junction box. Connect the phase wires (L1, L2, L3) from the THHN cable to the corresponding terminals in the junction box. Tighten the terminal screws securely.
Step 4: Connect the Female Bus Drop Cable Insert the female bus drop cable into the junction box and secure it with the provided strain reliefs. Connect the ground terminal on the female plug to the ground terminal in the junction box. Connect the L1, L2, and L3 terminals on the female plug to the corresponding terminals in the junction box. Crimp or wire nut the connections together.
Step 5: Connect the Male Bus Drop Cable Plug the male bus drop cable into the female connector. Ensure that the terminals are properly aligned and secure.
Step 6: Insulate and Seal Cover all exposed terminals with electrical tape. Securely close the junction box cover.
Additional Considerations: Use the correct gauge of wire for the load. Follow all applicable electrical codes and regulations. Ensure that all connections are tight and secure. Inspect and test the installation before energizing.* Consider using anti-oxidant paste on the bus drop cable terminals to prevent corrosion. Flag for review