A lug listed for CU only can be connected to which conductor?

A lug listed for CU only can be connected to which conductor?

• A. Aluminum
• B. Copper
• C. Copper or Aluminum
• D. Steel

Answer: (B)

A lug that is listed for copper only is designed and tested to be terminated with copper conductors. Copper and aluminum have different properties, and the lug’s materials, clamping mechanism, and torque requirements are specified to work with copper. Using aluminum can lead to poor contact, corrosion, creep, and a degraded connection, which the listing does not guarantee. Therefore, only copper conductors should be connected to a CU-only lug. Steel is not a suitable conductor for this purpose, and it would not meet the intended electrical and mechanical design of the lug.

A lug that is listed for copper only is designed and tested to be terminated with copper conductors. Copper and aluminum have different properties, and the lug’s materials, clamping mechanism, and torque requirements are specified to work with copper. Using aluminum can lead to poor contact, corrosion, creep, and a degraded connection, which the listing does not guarantee. Therefore, only copper conductors should be connected to a CU-only lug. Steel is not a suitable conductor for this purpose, and it would not meet the intended electrical and mechanical design of the lug.