Installation Overview

For systems with multiple Powerwall+ units, one Powerwall+ is designated as the Controller as it contains the site controller, and any additional units are designated as Expansion units. The Controller Powerwall+ is connected to the Backup Switch, and any Expansion Powerwall+ units are connected in a daisy chain via CAN wiring as described below. Additional Powerwall 2 units may also be connected in a side by side configuration as described in Side by Side Installations, or in a stacked configuration as described in Stacked Installations.

Maximum Distance Between Components

Install a Multi-Powerwall+ System

When installing a system with multiple Powerwall+ units, install each system component and connect the Backup Switch to the Controller Powerwall+ as it would be in a single Powerwall+ system.

To connect the Controller Powerwall+ to the Expansion Powerwall+ unit(s):

1. At the Expansion Powerwall+ unit solar assembly:
   1. Check the solar assembly part number. If it is 1538000-35-x, proceed to step 2. If it is 1538000-25-x, proceed to step 1b.

      

   2. Unplug the 12V power harness on the solar assembly site controller to disconnect 12V power.

      

      CAUTION

      If the 12V power is not disconnected from the Expansion Powerwall+ site controller, enumeration will be performed incorrectly during configuration.
2. Remove the left side cover from the battery assembly of each Powerwall+ to be joined.
   Note

   It may be necessary to remove the small plastic insert at the bottom of the covers to help with removal. Turn the cover to one side and rest it against the Powerwall+ chassis.

   

3. Using a T20 Torx bit, remove the wiring compartment covers from each Powerwall+.

   

4. Run 4-conductor communication cable from the Controller Powerwall+ to the Expansion Powerwall+.
5. At each Powerwall+:
   1. Remove the black heat shrink from the factory-installed battery whip.
   2. Remove and discard the terminating resistor.

      

   3. Strip the communication wire jacket about 3 inches and cut back the 12V and GND wires on either end of the communication wire. Cover the end of each exposed wire.
   4. Strip each CAN conductor 0.4 inches (10 mm), then insert the conductors into the green 4-pin connector on the end of the battery whip.
      Note

      Cut back the drain wire at the Controller Powerwall+. The drain wire should be terminated at the Expansion Powerwall+ battery assembly ground lug.

      

      

6. To ground the drain wire:
   1. Strip the end of the equipment grounding conductor and wrap the communication drain wire around the grounding conductor lead.
   2. At the Expansion Powerwall+, insert the drain wire and grounding conductor lead into the battery assembly chassis ground lug. The ground lug is identified with the following symbol:
   3. Tighten the screw in the ground lug to 4.5 Nm (40 lb-in).
   Note

   There will be a drain wire grounded in each pair of units in the chain (Backup Switch and Controller Powerwall+, Controller Powerwall+ and Expansion Powerwall+, etc.). For each pair of components, the drain wire is cut at the first component and grounded at the second.
7. Close all wiring compartments and replace all covers as described in Step 6: Close the Wiring Compartments and Replace the Covers.