Installation Day and Commissioning Checklist for a Home Battery
- Prepare access, the location and your internet connection before the visit.
- The installer must notify your network operator (DNO). MCS says this is within 28 days of installing a battery under G98, or before installation under G99.
- A backup configuration needs a backup gateway. Tesla states its Backup Gateway 2 is required for backup.
- Keep the warranty in mind: Tesla says Powerwall 3 must be reliably online for the full 10-year warranty.
- Do not accept a handover without settings explained and paperwork in your hands.
The installation day decides whether you end up with a battery that merely sits on the wall or one that is set up, tested and documented properly. Use this checklist to be ready, and to know what to ask for before you sign off.
Before the installer arrives
Agree the exact location with your installer when you accept the quote, then make sure the space is clear on the day. Our guide to choosing a home battery step by step covers the decisions that come before this one.
- Clear access to the consumer unit, the meter and the battery location.
- A working Wi-Fi or wired connection near the battery, since many systems need to be online.
- A decision on which circuits, if any, should stay powered in a power cut.
- Your tariff details, in case the installer sets time-based charging.
What happens on the day
Expect the system to be isolated, mounted, wired and then powered up. Tesla's care and maintenance page says to keep the area around the unit clear of debris so air can circulate, and not to install anything in front of or around it. That is worth checking before the installer leaves, because a tidy install can be spoiled by the shelving that goes up later.
If you are having backup, the installer should explain what the gateway does. Tesla's datasheet says its Backup Gateway 2 is required for backup and detects an outage so the battery disconnects from the grid.
Commissioning: what to see tested
Commissioning is the stage where the installer proves the system works and sets it up for your home.
Power up and connect
The battery shows as online in the app and linked to your account.
Settings explained
Mode, backup reserve and any scheduled charging are set and shown to you.
Backup tested
If you have backup, ask to see it work, not just be told it will.
Warranty registered
Confirm registration, and that the battery stays connected, since Tesla says Powerwall 3 must be reliably online for the full 10-year warranty.
Do not rush the handover
If something is unclear, ask on the day. It is much easier than chasing an installer later.
Paperwork to collect
The installer notifies the network operator, and you should be given confirmation. According to MCS, a battery under G98 is notified within 28 days of installation, while a battery under G99 needs permission before installation. Some operators use a different form, so ask which route applies to you.
Also ask for the electrical installation certificate, the warranty documents, the user guide and the installer's contact for faults. For how the UK rules fit together, see our UK country guide.
Common questions
Who tells the network operator about my battery?
The installer does. MCS says installers must notify the relevant DNO for batteries and solar, with timing depending on whether G98 or G99 applies.
Do I need to be home during the installation?
Someone should be available to give access and to take the handover. Agree this with your installer beforehand.
What if the battery is not connected to the internet?
It may still work, but Tesla says Powerwall 3 must be reliably connected for the full 10-year warranty, so check your maker's terms.
Related guides
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