I'm trying hard to get better at wiring diagrams. I'm using an ice machine at work to learn on, and the wiring diagram for it found online (ice o matic). One question that I have...is it common that a manufacturer to switch the neutral/common wire rather than the line side of a component to turn that component on/off? I know that's not commonly done with residential and commercial wiring, but when reading the schematic for this ice machine it seems it sometimes happens. Is this something that is common in hvac/r electrical design? Or is this never done, and I'm reading the schematics incorrectly?