Voltage rise

Voltage rise is the increase in voltage at an inverter's AC terminals that happens because the inverter generates current and pushes it out through the resistance of the wiring. For load circuits the same calculation is called voltage drop. For PV inverters it is called voltage rise because they supply power instead of using it. Getting the voltage rise right at design time helps prevent nuisance trips for voltage out of range when line voltage is high. Lower conductor resistance also means less power loss, less heat at terminals and better system performance. Enphase's method calculates the rise for each wire section separately and checks that the total stays below 2%. If you design to that limit, the small extra losses at terminals, connectors and breakers can be ignored. For the run from the IQ Combiner or PV subpanel to the point of common coupling, Enphase's tables give the maximum conductor lengths that keep that section at 1% rise. On the utility side, large amounts of PV can raise feeder voltage and make it fluctuate. This is worst near the end of long, lightly loaded feeders, and it affects power quality and voltage regulating equipment. If grid voltage or grid impedance at the connection point is too high, an inverter can disconnect from the grid. Some inverters also have a rise-in-voltage protection that watches the 10-minute average AC voltage.

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• sentence 1: support check: partial - Passage says voltage rises at the AC terminals because inverters generate electricity, but does not explicitly say current is pushed through wiring resistance, though it mentions conductor resistance.
• sentence 1: review: partial - The passage says voltage rises at each inverter's AC terminals because inverters generate electricity, but it does not state the mechanism of current pushed through wiring resistance. -->