@AmFlyer posted:The ZW-L has COMMON emblazoned above the 4 U terminals. Even as a degreed EE I have decided to accept modern usage of common to be anything that is wired together.
I know I stated my final $.02, but look in your electrical distribution box. The neutrals are tied together and unbeknownst to most the gnds are tied together and then the neutrals and Gnds are tied together.