Low meter power factor

A correctly wired revenue or production meter should show a power factor close to unity, between 0.9 and 1 in either sign (-0.9 to -1 or +0.9 to +1). Judge the meter power factor only while the system produces more than 50% of its rated output, and compare the meter phases with each other at the same time. A low power factor, or a mismatch between phases, usually points to a current transformer problem. If the reading falls outside the near-unity range, check that each voltage reference and its CT are on the same phase. Swapped phases are a common cause. Reversed meter or CT wiring is a related installation fault. Some inverters flag it as a reverse connection alarm, and the fix is to check whether the meter's input and output wiring is swapped. Meters can report power factor for each phase (L1, L2, L3). Some meters give both a true power factor and a displacement power factor, so check which one you are reading.

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• sentence 2: support check: partial - Passage mentions checking phases against each other and PF when producing over 50% of rated output, but 'at the same time' and 'only while' are slightly stronger framing; core is present.
• sentence 4: support check: partial - Check voltage ref and CTs matched phase-to-phase is stated, but 'swapped phases are a common cause' is not explicitly stated (only implied by the section title).
• sentence 6: support check: partial - Per-phase PF L1-L3 is listed and true vs displacement PF is described for an SEL meter, but 'some meters give both' and 'check which one' advice are only implied.
• sentence 4: review: partial - The check that voltage ref and CTs are matched phase-to-phase is stated, but the claim that swapped phases are a 'common' cause rests only on the section title. -->