Install Expansion Units with Powerwall 3

Figure 1. Powerwall 3 with Stacked Expansion Units
Figure 2. Powerwall 3 with Wall-Mounted Expansion
1 Powerwall 3
2 Powerwall 3 Expansion
3 Expansion Harness
Expansion units offer additional storage for Powerwall 3 systems. Key points about Expansion units include:
  • Function: An Expansion unit does not include an inverter; it is only additional storage (kWh)
    Note
    Expansion units do not have an LED. Wall-mounted Expansion units are installed with the same glass front cover as Powerwall 3, but the logo on the front will never light because there is no LED in the unit.
    Note
    Expansion units are not field serviceable.
  • Dimensions: The Expansion enclosure is the same height and width as Powerwall 3, but is 25 mm slimmer than Powerwall 3 (see diagram)
  • Mounting: Expansion units can be mounted individually, or ground-mounted in a stacked configuration behind a Powerwall 3
  • Expansion Connection: Expansion units can only be connected to Powerwall 3 or other Expansion units via the Expansion Harness (see Expansion Harness). Each unit (Powerwall 3 and Expansion) has (2) Expansion ports, one on each side of the enclosure
    Note
    The Expansion units are electrically paralleled with a Powerwall 3.
  • System Size: Up to (3) Expansion units can be connected to the Leader Powerwall 3
  • Compatible Powerwall 3 Units: Powerwall 3 units with Tesla P/N 1707000-xx-J or greater are compatible with Expansion units
  • Flexibility:
    • The Expansion Harness can be plugged in on either side of a Powerwall 3 or an Expansion unit
    • Powerwall 3 can be installed at either end of a chain of Expansion units
      Note
      When Expansion units are wall-mounted and connected on only one side of Powerwall 3, the maximum combined harness length is 4 m (see Allowable Harness Combinations for more information). When Expansion units are connected on both sides of Powerwall 3, there is no limit on the maximum combined harness length.
      Note
      Tesla recommends connecting the Expansion Harness to the port on the right side of the leader Powerwall 3 so that the model number label on the left side of the unit is not obscured.
    • Powerwall 3 can be installed in the middle of a chain of Expansion units
Figure 3. Powerwall 3 Dimensions Compared with Expansion Unit Dimensions
Note
Powerwall 3 and the Expansion unit are both 1105 mm tall when the glass front cover is installed.

Expansion Harness

The Tesla Expansion Harness is a non-metallic sheathed hard-use appliance cable assembly rated for indoor or outdoor installations. The cable uses an extruded TPE jacket that is moisture, flame, and UV resistant, and has a temperature rating of -40°C to 105°C. The harness is required for electrical connection between the Powerwall 3 and the Expansion units.

Note
Field wiring of the Expansion unit, alteration of the Expansion Harness (e.g. splicing), and/or routing the Expansion Harness through a wall or partition are prohibited.
Warning
Do not modify the Expansion Harness in any way. Doing so would result in product damage that could void the product warranty.
1 Sealing gasket
2 DC jaws
3 Communication ports
4 Grounding spikes (4)
5 Harness screw (T40)
6 Harness part number
7 Harness length identifier in part number
Table 1. Expansion Harness Options
Expansion Harness Part Number Expansion Harness Length
Tesla P/N 1875157-05-y 0.5 m
Tesla P/N 1875157-20-y 2 m
Tesla P/N 1875157-40-y 4 m
Note
When Expansion units are wall-mounted and connected on only one side of Powerwall 3, the maximum combined harness length is 4 m (see Allowable Harness Combinations for more information). When Expansion units are connected on both sides of Powerwall 3, there is no limit on the maximum combined harness length.
Note
Expansion Harnesses can be plugged into both the left and right ports on the Leader Powerwall 3.
CAUTION
The Expansion Harness ships in protective packaging from the factory.
  • Do not remove the protective packaging until ready to plug the Expansion Harness into the Expansion port
  • If the Expansion Harness is unplugged and needs to be set aside, place it back in the protective packaging
  • If the Expansion Harness is dropped or otherwise damaged, or if dust / debris enter its DC jaws and/or communication ports, do not use that Expansion Harness. Recycle it and use a new Expansion Harness
Note
The Expansion Harness can be painted under the following conditions:
  • The paint is latex or acrylic-based (do not use an oil-based paint)
  • Only the harness cable is painted; do not paint the connectors, or any part of Powerwall 3 or Expansion

A primer coat prior to painting is recommended to help with adhesion and bonding.

Expansion Mounting Configurations

Stacked Configuration Wall-Mounted Configuration
Kit P/N Tesla P/N 1978070-xx-y Tesla P/N 1978069-xx-y
Included Accessories See Powerwall 3 Stacking Expansion Kit See Powerwall 3 Wall-Mount Expansion Kit
Expansion Harness (ordered separately, see Expansion Harness for part number location)* Tesla P/N 1875157-05-y Tesla P/N 1875157-05-y
Tesla P/N 1875157-20-y
Tesla P/N 1875157-40-y
Note
When Expansion units are wall-mounted and connected on only one side of Powerwall 3, the maximum combined harness length is 4 m (see Allowable Harness Combinations for more information). When Expansion units are connected on both sides of Powerwall 3, there is no limit on the maximum combined harness length.
Expansion Harness Straps Not required Tesla P/N 1730711-xx-y, some are included in accessory bag but additional straps can be ordered (Bridgeport US-6171 strap)
Installation Instructions Install Stacked Expansion Units Install Wall-Mounted Expansion Units

*Expansion harnesses can be plugged into both the left and right ports on the Leader Powerwall 3. See Install Wall-Mounted Expansion Units for a table of all allowable harness combinations.

Powerwall 3 Stacking Expansion Kit

1 1738120-xx-y Wall bracket
2 1983307-xx-y (4) mounting bracket shims
3 1978075-xx-y (4) Torx T40 mounting bracket bolts
4 1978071-xx-y (6) fir tree plugs, used to fill in the fastener holes on the top and sides of the enclosure
5 1978068-xx-y Fan front cover

Powerwall 3 Wall-Mount Expansion Kit

1 1738120-xx-y Wall bracket
2 1730711-xx-y (9) Straps for Expansion Harness cable management (Bridgeport US-6171 strap)
3 1763418-xx-y Glass front cover
4 1857363-xx-y (6) M6 fasteners for front cover