Wiring:The iWave-R has a patented universal voltage 24VAC to 240VAC input ability. The black wire (marked ‘AC’ on label) is for 24VAC to 240VAC voltage input. The white wire (marked ‘N’ around the label) may be the neutral leg for 24VAC or 120VAC; or another hot leg for 208/240VAC. https://npo-authority57789.liberty-blog.com/28712932/the-ultimate-guide-to-donorsearch