In this guide 6 sections
Claims arrive without history because the factory keeps records by batch, in separate files, while the customer reports by serial number. Nobody joins the two at dispatch. A unit record that holds lots, test results and firmware against each serial closes the gap, and the warranty clerk can answer from one screen, not by phone.
The claim speaks serial numbers, the factory speaks batches
A site engineer reports that inverter 4471 trips on grid fault every afternoon, and your records show only that a batch of that model left in March. Between the two there is nothing.
Production data is usually kept by work order, dispatch by invoice, and service in a ticket sheet, so no two of them share a key. The warranty manager phones around.
That is slow. It is also unfair to the customer, since a claim that cannot be judged tends to be settled by habit and not by evidence.
What a claim needs to be judged
A module claim for power loss or a delaminating corner needs the cell lot, the EVA roll, the laminator recipe and the original flasher result. An inverter claim needs the firmware version, the board lot and the burn-in log, because a trip that appears only after an update points at software, not hardware.
A battery claim needs the cell batch, pack grading data, the BMS configuration file and the acceptance test, or you cannot tell a field fault from a build fault.
Resist fields you will never read. Start with the questions you would put to a cell or inverter supplier when passing a claim upstream, and add a field only when a real claim needed it.
- Module: cell lot, EVA roll, glass batch, flasher file, EL image
- Inverter: firmware version, board lot, burn-in log, certificate
- Battery: cell batch, grading data, BMS configuration, FAT report
- All: dispatch date, invoice, site address, commissioning date
Where the history goes missing
The first leak is the test PC. The flasher saves results in a folder named by date, so a year later nobody knows which file belongs to which serial. The second leak is firmware. Engineers flash a fix on the line, write down nothing, and the unit leaves with a version that no document in the factory mentions.
The third is rework. A module goes back for a replacement junction box, its second life is never attached to the first, and the record shows a clean unit with a hidden past.
Supplier changes break things too. Cells from a new vendor start arriving on a Monday, the old lot numbering rule no longer fits, and nobody updates the sheet until the first complaint arrives.
One unit record per serial
Key one record on the serial. Production stations write into it, dispatch adds the customer and invoice, commissioning adds the site and date, and service appends every ticket afterward.
Keep history read-only. Corrections are new entries with a reason, so the original value survives, which matters when a cell supplier disputes a claim you pass upstream. Make the repair bench log every swapped junction box, cell string or control board against the original serial, so a second life stays attached to the first one.
One search should tell the whole story. If a warranty clerk still needs three screens and a phone call to reach the build history of a single serial, the record is incomplete.
Start the claim form from the record
The serial does the lookup. The clerk then adds only what the field supplies, which is the fault description, photos, site conditions and any logger data from the inverter or battery. Photos from site, inverter event logs and the installer’s name arrive with the claim, while the build side arrives from the record without a phone call to the factory.
Add a decision field with set reasons, such as installation fault, grid issue or build defect, and the pattern soon shows which lots deserve a closer look. Firmware versions deserve the same scrutiny.
Take your last ten claims and try to rebuild each build history by hand, from flasher folders, work orders and dispatch notes. Every gap is a field.
Unit record field list
One page, three blocks. Each block lists the build fields to capture against a serial, such as lots, test files and firmware or configuration versions. Two columns beside each field name the station or person who writes it and where the file lives today, which is usually a test PC or a shared drive. A last block lists decisions.
Open a blank worksheet to printQuestions owners ask
Why can’t we just ask the production team?
They can help, but memory fades and staff change, and a claim two years after dispatch needs a record, not a recollection of which line ran that week.
Do inverters need build records as much as modules?
Yes, and firmware matters more. Two inverters of the same model can behave differently if one runs a later release, and only the unit record shows which release each one left the factory with.
How long should build history be kept?
It depends on the contract. Keep it until the longest warranty you offer has expired and the last claim against it has settled, and check your own contracts, because their terms set the limit.
Can we rebuild history for units already shipped?
Yes, for some units. Match old flasher files and work orders to serials where you can, and mark the rest as unknown, because a partial record is still better than none.