Option P3 (per-phase outputs) for the WattNode® Pulse meter provides three separate pulse outputs on terminals P1, P2, and P3—one pulse output channel for each of the three measurement phases.

Option P3 is fully documented in the main WattNode Pulse Manual.

  • Example part numbers: WNB-3Y-208-P Opt P3 or WNB-3Y-480-P Opt P3

Option P3 Applications

  • Low Cost metering of motor loads
  • Measuring three single phase 120 plug loads
  • Measuring three single phase 277 volt lighting loads

Option P3 allows very low cost measurements for three-phase applications where cost is more important then accuracy. With reasonably well balanced three-phase loads, such as a motor, good accuracy can be achieved by measuring only one phase of a three phase service and multiplying the reading by three. This can reduces metering equipment costs by two-thirds compared to using three meters and nine current transformers.

A meter with Option P3 can also monitor three separate single-phase circuits using one WattNode meter, at full rated accuracy. This is useful when monitoring 120 volt branch circuits or 277 volt lighting circuits. Since each of the meter’s three phases is an independent single-phase watt meter, the ØA, ØB, and ØC voltage inputs and corresponding CT inputs can measure three loads powered from the same phase or any combination of phases.

Note: with Option P3, CTs with different full scale current ratings can be connected to each phase.

See Also

Keywords: submeter, sub-meter, plug loads, lighting loads, bus bar