Tesla Powerwall › grid voltage and power quality
Grid voltage sags below 138V, forces Powerwall backup
reported more than once
Symptoms
- On hot afternoons or during general utility strain, incoming line voltage sags to the 100-138V range on a nominal 120/240V service
- A Backup Gateway responds by forcing the Powerwalls onto backup power and disconnecting from the grid, which also times out the solar inverter for minutes at a time and can repeat continuously
- A paired solar/battery inverter (SolarEdge, Delta) logs a grid-undervoltage or line-to-neutral overvoltage fault and stops producing or discharging until the utility corrects the voltage
- Over time the same sag can contribute to a separate inverter's outright failure
Alerts and codes
SolarEdge Error 18x22L1N over voltage
The cause and the fix
Subscribers see the cause, the fixes that worked and who did them, part numbers and recent prices when a part is involved, and the field reports behind this entry.