715 Electrical Safety for Technicians and Supervisors

Safe Work Practices

Insulating Terminal Lugs

Insulating terminal lugs, also known as insulated cable lugs or terminals, are connectors crimped onto the ends of wires with built-in insulation (often made of materials like PVC or nylon) to prevent accidental contact with live parts, reducing the risk of electric shock, short circuits, or arcing. The insulation covers the barrel and sometimes extends over the connection point, ensuring no exposed metal that could cause leakage or unintended grounding.

Sample Step-by-Step Procedure for Using Insulated Terminal Lugs

• Verify the circuit is de-energized and locked out when possible before beginning work.
• Select the correct size insulated terminal lug for the wire and application.
• Strip the wire insulation to the proper length without damaging the conductor strands.
• Insert the stripped conductor fully into the terminal lug barrel.
• Use the correct crimping tool to crimp the lug securely onto the wire.
• Inspect the crimp to confirm it is tight and the conductor cannot be pulled out.
• Apply additional insulation, such as heat-shrink tubing or insulating sleeves, if required for the environment.
• Install the lug onto the terminal or equipment connection point.
• Ensure no exposed metal is present and the insulation fully covers the connection.
• Wear appropriate PPE, such as insulated gloves and safety glasses, during installation.
• Inspect installed lugs periodically for signs of damage, overheating, or corrosion.

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