Watt-VAr makes the inverter or battery absorb or inject reactive power according to its own real power output, following a programmable curve. In the default IEEE 1547-2018 settings table, the Watt/VAR function is switched off by default. On Tesla commercial systems, Watt-Var is an open-loop response to real power measured at the POI meter. The reactive power it adds is summed with any Direct Reactive Power command. The Tesla curve has an enable flag, six per-unit real power points and six per-unit reactive power points, plus a response time constant for reaching 95% of the requested reactive power. A read-only output register shows the added reactive power. On Tesla systems, the real power points are scaled to the battery's nominal discharge power and the reactive power points to its nominal reactive power. The Yaskawa Solectria PVI 25TL-208, PVI-36TL-480-V2, PVI 50TL-480 and PVI 60TL-480 list Watt-VAr among their functions. The smart-grid feature list of the CPS SCA25KTL-DO-US-208 does not include it.
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- sentence 1: support check: partial - Passages say the response follows a programmable curve based on real power measured at the POI meter, not the inverter's own output.
- sentence 1: review: partial - The passages back absorbing or injecting reactive power along a programmable curve, but they say the response follows the system's real power dispatch measured at the POI meter, not the device's own output, and they mention only the battery, not…
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