what does cu mean in electrical terms
Check out some tips on how to choose switches and outlets while avoiding pitfalls at Kyleswitchplates.com. Devices marked CU-only are intended for use only with copper wire (wire systems with solid-core copper wiring) and should not be used with aluminium electrical wiring.heck out some tips on how to choose switches and outlets while avoiding pitfalls at Kyleswitchplates.com. Devices marked CU-only are intended for use only with copper wire (wire systems with solid-core copper wiring) and should not be used with aluminium electrical wiring.