Wiring:The iWave-R has a patented common voltage 24VAC to 240VAC enter capability. The black wire (marked ‘AC’ on label) is for 24VAC to 240VAC voltage input. The white wire (marked ‘N’ within the label) is the neutral leg for 24VAC or 120VAC; or the other sizzling leg for 208/240VAC. https://i-wave90122.pointblog.net/facts-about-npo-authority-revealed-69800030