split-phase 120/240V, three-phase, and where grounding fits in
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tap two points on the diagram
Same math, on a physical calculator
F4√ — find √3 ≈ 1.732 first — that constant is the base of every 3-phase phase-to-phase calculation
C4× — multiply √3 by the phase-to-neutral voltage to get WYE phase-to-phase voltage
C4× — split-phase is simpler: 2 × the leg voltage is the full winding, no √3 involved at all
D4÷ — high-leg delta's center tap: divide the phase voltage by 2
Grounding vs. neutral — a separate question from phases
Neutral
A current-carrying conductor — under normal operation, it's doing real work bringing current back to the source.
Bonded to ground at exactly one point: the main service panel.
In a subpanel, neutral and ground must stay on separate buses — bonding them again creates a dangerous parallel current path.
Ground
Carries essentially zero current under normal conditions — its job is to sit idle.
If a hot wire ever faults against a metal enclosure, ground gives that current a fast, low-resistance path back to the panel — that's what trips the breaker instead of a person becoming the path.
Every metal box, tool casing, and appliance frame gets tied to this system for exactly that reason.
Educational reference only — real panel work must follow the NEC and local code, and should be done or verified by a licensed electrician. This tool teaches the concepts, not code compliance.
Session Log Entry — what this Wrap Up wrote to the Ledger