2025-09-22

Multiple Powerwall 2/Powerwall+ Units to Powerwall 3 Upgrade

Prerequisites

Before visiting the site, ensure that the updated planset is available (indicating that a site redesign was completed). The new site design should be compliant with all existing permits, or re-permitted according to the new design.

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Warning
This procedure is to be performed on a de-energized Powerwall.

Hazards

Figure 1. Shock
Figure 2. Arc Flash
Figure 3. Cut Hazard

Safety and PPE

  • Safety glasses (ANSI Z87.1 or EN 166)
  • Cut-resistant gloves (ANSI Cut Level 3 or EN 388 Level C)
  • Safety rated shoes with leather upper

General Equipment

  • Paint pen

Remove

  1. Complete the Powerwall 2 Lockout/Tagout or Powerwall+ Lockout/Tagout de-energize the system.
  2. Follow the steps below to remove all the Powerwall units on the site.
    Warning IconA warning icon, calling your attention to a possibly risky situation
    CAUTION
    ALL Powerwall 2 or Powerwall+ units must be replaced, as Powerwall 3 is not compatible with older generations of Powerwall. A site cannot include a mix of these.
  3. If replacing a Powerwall+, follow the Powerwall+ Solar Assembly Removal procedure to remove the PVI portion of the system from the wall.
  4. Follow the Removing Powerwall 2 procedure procedure to remove the standalone Powerwall 2 units and the battery portion of the Powerwall+ units.
  5. Remove the screws securing the Powerwall mounting bracket to the wall.

    Remove the mounting bracket and clean the wall surface from any sealant or dirt.

  6. Patch the holes created from the mounting bracket hardware using a method suitable for the wall surface.
  7. Remove the conduit fittings and determine the changes needed in the conduit run to accommodate the new Powerwall system. In most multi-unit installations, the total number of AC connections will be reduced by using DC Expansion units.

    In most cases where the run is short, the conduit should be removed and new conduit should be run.

    In cases where the conduit can be reused or extended, make sure that the fittings are appropriate and all the connections are compliant with local code.

    Seal any knockout holes left by removed conduit using the appropriate plugs and ensure the seal is watertight.

Install

  1. Use the guidelines below to plan the installation locations of the new units, which generally should mirror the locations of the previous Powerwall units.
    1. When using DC Expansion units, be mindful of the distance restrictions. If the removed Powerwall units are spaced further apart than allowed by the Expansion harness, they should be relocated within the harness's reach.

      Refer to Wall Mount an Expansion Unit in the install manual for more information.

      Informational PurposesAn informational icon, calling your attention
      Note
      Note that there is a combined maximum distance restriction.
    2. If the removed Powerwall units were installed in a stacked configuration, the replacement units should also be stacked.
      Warning IconA warning icon, calling your attention to a possibly risky situation
      CAUTION
      Note that in cases where multiple Powerwalls are stacked, the increased load of PW3 may exceed the threshold of the wall. Powerwall 3 itself can support up to 4 units in a stack.
    1. Do not mount multiple brackets on the same studs as this might overload them. If units need to be relocated, they must not be placed above or below another unit on the same stud.
    2. Before mounting any units, create a diagram of the planned setup. Each site has a unique configuration of Powerwall 3 and Expansion units and the layout should be optimized to minimize cable runs.
      • Each Powerwall must have an AC connection to a dedicated breaker in the load center.
      • For sites with more than two units, a communication wire should be run between the Powerwall units.
      • DC Expansion units only require the DC Expansion harness connected to a Powerwall unit or another Expansion unit to form a chain.

      Rearrange the units as needed to ensure the cleanest possible wire runs and avoid excessive use of conduit.

    3. In a Powerwall+ setup, the solar wires that previously ran to the solar assembly must now be routed to the Powerwall 3. This should be taken into consideration when selecting a mounting location.

      This requirement does not apply if standalone solar inverters are used instead.

  2. Follow the instructions in Powerwall 3 Installation Manual with Backup Gateway 2 to install the new Powerwall 3 and Expansion units.
    1. When mounting the Powerwall 3 and DC Expansion brackets, note that the bracket differs in both size and position compared to Powerwall 2. Reusing the existing mounting holes will cause the Powerwall to sit in a different position on the wall. Refer to the diagram below for bracket dimensions relative to the edges of the unit.
    2. The wires and breakers need to be re-run. Follow the guidance in the installation manual to run the correct gauge wire and the proper overcurrent protection.
  3. If a Rapid Shutdown Device (RSD) is connected to the Gateway 2, it must be moved to the Powerwall 3.

    Follow the instructions in STEP 8: Install System Shutdown Switch Where Required in the Powerwall 3 Installation Manual to switch the RSD from the Gateway to the Powerwall 3. The jumper should be removed from the Powerwall 3 and installed in the RSD port of the Gateway 2, from which the switch wire was removed.

    Informational PurposesAn informational icon, calling your attention
    Note
    The RSD may need to be replaced if multiple Powerwall 3 units are being installed, as the switch requires a dedicated terminal for each Powerwall in the system.
  4. Once all conductors are installed, follow these steps to commission the new unit.
    Informational PurposesAn informational icon, calling your attention
    Note
    Do NOT complete the Powerwall 3 commissioning procedure outlined in the Powerwall 3 Install Manual. Instead, use the steps provided below which detail several deviations from the standard commissioning procedure.
  5. Turn on all the Powerwall 3 switches and connect to the leader Powerwall 3 using the Device Setup interface in Tesla One app.
    Informational PurposesAn informational icon, calling your attention
    Note
    After turning on the unit, allow 2 - 3 minutes for the Wi-Fi signal to begin broadcasting.
  6. Navigate to the Networking tab and connect the unit to the customer's Wi-Fi, if available. Refer to Configure Internet Connection section in the Powerwall 3 Quick Guide for more information.
  7. On the Software tab, check for software updates and download any available updates.
  8. Navigate to the System tab and verify that the Gateway is communicating with the Powerwall 3 without any errors. If the communication is not established, inspect the CAN wiring between the units.

    Verify that all installed units are present and displaying no errors. If any units are missing or showing any errors, troubleshoot the issue before proceeding.

    Refer to the Check Connected Devices page for more information.

  9. If applicable, set the Powerwall's maximum power/current output using instructions in the Configure Powerwall 3 Maximum Power / Current Output section.

    This value must be set to comply with permit requirements. Refer to the site design to determine the correct values.

    Warning IconA warning icon, calling your attention to a possibly risky situation
    Warning
    This step is critical. Failure to complete it can result in electrical faults in the wiring due to overcurrent. Do NOT start the system before setting this limit.
  10. Document the configured limit on the product label on the left side of the Powerwall unit. Use a paint pen to mark the box corresponding to the limit set.
  11. Navigate to the Metering tab to confirm the meter(s) are configured correctly. Powerwall 3 only supports Tesla Remote Meters or wired meters, so any third-party meters, such as Neurio meters, must be replaced with a Tesla Remote Meter.
    Replace meters as necessary and configure them in the Metering tab using the instructions in the Configure Meters and CTs section.
    Informational PurposesAn informational icon, calling your attention
    Note
    Replacing a meter with a Tesla Remote Meter is common at sites with AC-coupled solar or non-backup loads. Follow this guidance to correctly set up the meters: Install Tesla Remote Energy Meter and CTs.
    Informational PurposesAn informational icon, calling your attention
    Note
    If Meter Y is used in the Gateway, it does not need to be replaced.
  12. Navigate to the Settings tab to set the grid code and solar installation type. If the site requires additional settings, set those under the Advanced Settings option.

    Refer to Configure Settings for more information.

  13. Complete the instructions on the Registration tab and register the system to the customer using the same account that was previously used to set up the site.
  14. Start the system.
  15. Before leaving the site, inform the homeowner that their unit has been replaced with a Powerwall 3 and explain the differences between their old system and the new one.

    Additionally, advise the customer that some app settings might have been reset with the swap and to check their configurations if they have been changed from default values.