Wiring:The iWave-R incorporates a patented common voltage 24VAC to 240VAC enter functionality. The black wire (marked ‘AC’ on label) is for 24VAC to 240VAC voltage input. The white wire (marked ‘N’ on the label) is the neutral leg for 24VAC or 120VAC; or the other warm leg for 208/240VAC. https://i-wave25689.topbloghub.com/34815622/donor-search-things-to-know-before-you-buy