What a battery commissioning handover pack should contain

The day a battery is commissioned, attention is on the system going live. The paperwork handed over that day matters for much longer: it is what your insurer, your auditor, the network operator and the next engineer will ask for. This post explains what a handover pack for a commercial battery should contain and why each document earns its place. For the process that produces it, see the guide to battery storage commissioning.

Why the pack matters after the installer has gone

Most problems with a commercial battery surface months or years after commissioning: a warranty claim, an insurer’s survey, a protection trip nobody can explain, or an extension to the system. Each of those starts with the same question: how was it installed and tested? If the answer is in a folder on site, the question takes minutes. If it is not, someone pays for an engineer to reconstruct it.

The electrical certificate and its schedules

A new electrical installation is certified with an Electrical Installation Certificate, supported by schedules of inspections and of test results. The IET publishes model forms for BS 7671:2018+A4:2026, the edition that added a chapter for stationary battery installations. Check that the certificate covers the battery circuits specifically, that the designer, installer and inspector have each signed their section, and that the schedules carry real test values rather than ticks.

These results become the baseline for every later inspection: a periodic report years from now is far more useful when it can be compared against measured values from day one.

The G99 records

How the grid connection was proved depends on the system’s size under Engineering Recommendation G99. According to the Energy Networks Association’s Distributed Generation Connection Guide, a system below 1 MW (Type A) has its commissioning results recorded on the Installation Document, which must reach the network operator within 28 days of the date of commissioning, or on the day if the operator witnesses the tests. Systems of 1 MW and above move through Energisation, Interim and Final Operational Notifications.

Keep copies of whatever applies. If the network operator later queries an export reading or you want to extend the system, these records show what was agreed and proved.

Settings, drawings and manuals

• Protection and control settings, as commissioned. Not the design intent; the values actually set on site, including any export or import limits. A settings change without a record is how sites drift out of compliance with their connection agreement.
• As-built drawings and the single-line diagram. Cable routes, isolation points and the location of every emergency stop. They are what an engineer, or a firefighter, needs first.
• Operating and maintenance manuals, including the manufacturer’s maintenance intervals and any firmware or software update arrangements.

Warranty and fire safety records

Register the warranty in your company’s name and keep the confirmation. Read what it requires of you: a battery warranty can depend on maintenance being carried out and recorded, and on who installed the system.

Ask for the commissioning records of the fire detection and any suppression system, and for an emergency response plan for the site. For larger open-air systems, the National Fire Chiefs Council guidance expects an outline battery safety management plan and emergency response plan to be developed with the local fire and rescue service. Even on a smaller site, a one-page plan saying how to isolate the battery and who to call is worth having. The battery storage fire safety regulations guide sets out the standards behind those records.

Training and contacts

The handover should end with the people who will run the system knowing how to: read its status, respond to an alarm, isolate it safely and report a fault. Get a named contact for faults and a response arrangement in writing, especially if you are relying on the battery for backup power.

If something is missing

Hold back the final sign-off (and, if your contract allows, the retention) until the pack is complete. A missing certificate is far easier to obtain while the installer is still on the job. If you are still choosing an installer, put the handover list in the tender; the installer checklist covers the other questions to ask. And if you want quotes, request them here: your enquiry is passed to installers who cover your area, and this site is not one of them.