Powerwall 3 System Overview

Powerwall 3 is a fully integrated solar and battery system. The home's PV array is connected directly to Powerwall 3, which converts solar energy and stores it for future use. Powerwall 3 is installed with Backup Switch to control the system's connection to the grid and monitor home energy consumption.

Figure 1. Example System Diagram

The following table outlines the key Tesla components in a standard Powerwall 3 system.

Tesla Components

Tesla Part Numbers Component Description

1707000-xx-y

Powerwall 3 is an integrated solar and battery system that converts energy from solar panels or Solar Roof to be used by the home, and stores excess energy for future use. Every system contains at least one Powerwall 3, with additional Powerwall 3 units and/or Expansion units installed depending on the home’s solar system size and/or energy consumption.
1807000-xx-y

Expansion unit is mounted behind Powerwall 3 unit

Powerwall 3 Expansion is a battery that provides additional storage for a Powerwall 3 system. Because the Expansion does not include an inverter, it cannot be installed without Powerwall 3. Solar cannot be connected to an Expansion unit.
MCI-1 The Tesla Mid-Circuit Interrupter (MCI) is a device installed in the PV array to stop solar production when:
  • Rapid Shutdown (RSD) is initiated
  • Loss of inverter (Powerwall 3) power is detected
  • A system fault is detected
MCIs, which are normally closed devices, open in either of these conditions, bringing DC voltages to safe levels within 30 seconds.
MCI-2

1624171-xx-y
Backup Switch monitors energy usage and manages the transition to and from backup operation.