Connectors marked with what designation are suitable for use with aluminum, copper, or copper-clad conductors?

Connectors marked with the designation that includes both aluminum and copper (AL/CU) are specifically designed to accommodate both types of conductors. This labeling indicates that the connector has been tested and certified for use with both aluminum and copper conductors, which often have different properties and requirements regarding thermal expansion, conductivity, and corrosion susceptibility.

Using connectors that are rated for both types of conductors ensures safe and effective electrical connections, minimizing the risk of failure or overheating. This rating is crucial when dealing with mixed wiring systems or when aluminum conductors are in close proximity to copper conductors, which can be common in various applications.

In contrast, connectors marked for only one type of conductor would not provide reliable performance if applied to a different type, potentially leading to safety hazards or system failures. Thus, the AL/CU designation is important for ensuring the versatility and safety of electrical installations.