These are the phase-to-ground (ph-gd) and phase-to-phase (ph-ph) low voltage levels typically available in Ontario
120 Volts 1-phase ph-gd
120/208 Volts 3-phases, ph-gd/ph-ph
120/240 Volts typical single family residence supply, effectively 2-phases @ 180 degrees, ph-gd/ph-ph
277/480...