Switches rated 20 amps or less and designed for the direct connection of aluminum conductors shall be marked ___.

Switches rated 20 amps or less and designed for the direct connection of aluminum conductors shall be marked ___.

• A. Cu/Al
• B. ALR
• C. AL
• D. Co/Alr

Answer: (D)

The topic here is how devices are marked to show they can be connected directly to aluminum conductors. When a switch is rated for 20 amps or less and is intended for direct connection to aluminum conductors, the marking used on the device is CO/ALR (Copper-Aluminum Rated). This label communicates that the device is suitable for use with both copper and aluminum conductors and that it is specifically approved for direct connection to aluminum wiring. The ALR designation alone conveys aluminum direct-connection suitability, but CO/ALR makes explicit the copper/ aluminum compatibility in one combined mark, which is the standard wording expected in this context.

The topic here is how devices are marked to show they can be connected directly to aluminum conductors. When a switch is rated for 20 amps or less and is intended for direct connection to aluminum conductors, the marking used on the device is CO/ALR (Copper-Aluminum Rated). This label communicates that the device is suitable for use with both copper and aluminum conductors and that it is specifically approved for direct connection to aluminum wiring. The ALR designation alone conveys aluminum direct-connection suitability, but CO/ALR makes explicit the copper/ aluminum compatibility in one combined mark, which is the standard wording expected in this context.