Optional: High Impedance Mode
High Impedance Mode can be toggled on to improve system performance on sites with high
grid impedance. To enable the feature:
- Navigate to the Advanced Settings menu.
- Select Off-Grid Settings.
- Toggle on High Impedance Mode.
CAUTION
The installer is still responsible for ensuring that the wiring in the
home is safe and installed according to local regulations.
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Determine Whether High Impedance Mode is Needed
Select Do I need this? if unsure whether to toggle on High Impedance Mode. Tesla One will detect the number of Powerwalls on-site and ask whether the Electric Service Size is above or below a certain threshold to determine whether to recommend High Impedance Mode.
Electric Service Size Calculation
Tesla One will recommend the overrides if the electric service size is ≤ 40A per Powerwall per phase.
Examples:
- 4x Powerwalls on a 200A connection: Override not recommended, because there is 50A per Powerwall
- 5x Powerwalls on a 200A connection: Override recommended, because there is 40A per Powerwall
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