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Supply polarity, three phase: ten readingsWhich readings should be 400 volts?
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Same idea, more combinations. Between any line and neutral, or any line and earth, it’s 230 V. Between two lines, 400 V. Neutral to earth, zero.
| Readings | Expect |
|---|---|
| N – L1 · N – L2 · N – L3 | 230 V each |
| E – L1 · E – L2 · E – L3 | 230 V each |
| N – E | 0 V |
| L1 – L2 · L1 – L3 · L2 – L3 | 400 V each |
Any other combination is incorrect supply polarity, and the same rule applies: stop.
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