KRL Power supports commercial & industrial energy-storage projects where a shipment should be released only after the supplied system is traceable to the contracted design. From a 10-year C&I energy-storage perspective, a BESS factory acceptance test is not a factory tour or a generic demonstration. It is the EPC buyer’s last controlled opportunity to verify the exact equipment, evidence, protection logic, interfaces, and open issues before ocean freight, site installation, and commissioning make correction slower and more expensive.
For an EPC team, the objective is simple: leave the factory with an acceptance record that proves what was inspected, what passed, which evidence remains outstanding, and who owns every remaining action. That record should match the purchase order, approved submittals, single-line diagram, bill-of-material boundary, communication architecture, and project-specific test plan. It should not rely on photographs of a similar cabinet or a verbal assurance that the production unit is equivalent.
- Confirm the exact serial numbers and model numbers before any functional test begins.
- Agree pass, fail, witness, and re-test rules before the FAT date.
- Record actual observations, measured values, software versions, and exceptions.
- Release equipment only after the agreed closure path is documented.
- Keep FAT evidence separate from later site acceptance and grid-commissioning obligations.
FAT Scope and Contract Boundary
The most costly FAT failures usually begin before the first test. The buyer arrives with a broad idea of the system; the factory demonstrates what is available; neither party compares the final production configuration against a controlled acceptance schedule. Avoid that gap by attaching the FAT plan to the contract or approved technical submittal. The plan should name the equipment boundary, test sequence, instruments, document set, acceptance criteria, witness rights, deviation process, and release authority.
| FAT boundary | EPC buyer should verify | Evidence to retain |
|---|---|---|
| Equipment identity | Model, serial number, quantity, configured options, and approved substitutions | Photographs, nameplate register, packing list, and signed configuration sheet |
| Electrical architecture | Battery, PCS, protection, auxiliary supply, emergency stop, grounding, and interface boundary | Approved SLD, wiring records, settings list, and test record |
| Controls and communications | BMS, EMS, PCS, SCADA or gateway interface, alarms, user roles, and protocol boundary | Software-version register, point list, screenshots, and communication test result |
| Project documents | Datasheet applicability, certificates, manuals, shipping documents, and warranty boundary | Document index with revision, model applicability, and unresolved items |
KRL’s public C&I portfolio includes cabinet and container configurations with different power, energy, cooling, protection, and parallel-operation boundaries. A buyer may use published pages as a starting point, including KRL commercial & industrial energy-storage solutions, but a published family description is not FAT proof. The FAT record must identify the actual quoted configuration, including the final interfaces and project options.
Pre-FAT Document Package
Ask for the document package early enough to review it before travel or remote witnessing. The purpose is not to collect the largest possible folder. It is to identify the documents that control design, quality, safety, shipment, and handover. If a document is still preliminary, mark it as preliminary and state the required final revision date.
- Approved technical specification, purchase-order scope, and deviation log
- Model-specific datasheet, nameplate information, BOM boundary, and single-line diagram
- Battery, PCS, BMS, EMS, fire-protection, cooling, and auxiliary-system interface descriptions
- Certificate copies with the applicable model, configuration, and destination-market boundary identified
- Factory test procedure, calibrated-instrument list, test forms, and pass/fail criteria
- Packing method, lifting information, dangerous-goods documents, transport responsibility, and preservation instructions
- Commissioning plan, site acceptance boundary, warranty process, and technical-escalation contacts
Treat certificate claims carefully. A certificate that names a different model, a different enclosure, or a cell-only sample cannot automatically validate the complete delivered system. The same principle applies to public performance statements. KRL pages describe functions such as BMS, PCS, EMS, cooling, fire protection, and generator interfaces in different solution contexts; the relevant question is whether the exact system configuration and project document set include them. For component roles, use KRL’s BMS, PCS, and EMS overview as background, then request the project-specific interface map.
Production Identity and Build Quality
A sound FAT begins with identity, then moves to workmanship. The buyer should be able to connect the cabinet in the test bay to the shipment list, final BOM boundary, and contractual configuration. This is especially important where a system combines battery modules, PCS, PV inputs, liquid or air cooling, fire equipment, an EMS, and a generator interface. A successful power-on demonstration does not replace this traceability check.
- Match cabinet, battery-rack, PCS, and controller serial numbers to the acceptance register.
- Check enclosure condition, labels, cable routing, terminations, grounding, access panels, seals, and service clearances.
- Verify that installed options match the approved BOM and that substitutions are listed in writing.
- Confirm cooling, fire-protection, and auxiliary-equipment interfaces against the approved drawings.
- Record missing labels, workmanship defects, shipping-protection gaps, and incomplete covers as punch-list items.
When selecting the sample depth, use project risk rather than a convenient demonstration. A single cabinet may be sufficient for a repeatable batch only if the contract defines the production-control basis and traceability. For a first-of-kind integration, custom EMS interface, or critical-load project, the buyer may require a more detailed witness scope. EPC teams evaluating cabinet architecture can also review KRL’s energy-storage inverter guide, while keeping the FAT acceptance criteria tied to the contracted inverter model.
Electrical Protection and Functional Tests
Functional testing should prove the agreed control sequence, not merely show that a screen turns on. The test procedure must define preconditions, expected response, measured result, and restoration method for each sequence. Site grid studies, final utility permission, and full-load site performance may remain SAT responsibilities; record that boundary instead of trying to simulate every site condition in a factory bay.
| Test area | FAT acceptance focus | Release decision |
|---|---|---|
| Power-up and shutdown | Defined start-up, normal stop, emergency stop, alarm reset, and safe recovery sequence | All required states respond as specified and are recorded |
| Protection chain | Configured alarms, trips, interlocks, communication-loss behavior, and emergency-stop boundary | Each witnessed function has a pass/fail record and unresolved functions are blocked from release |
| Battery and PCS control | Status exchange, enable logic, operating limits, and fault indication at the agreed interface | Evidence identifies software version and tested configuration |
| Communications | Required BMS/PCS/EMS or SCADA points, timestamps, command authority, and alarm visibility | Point list is witnessed or a documented remote/SAT closure route exists |
| Auxiliaries | Cooling, fire-system interface, heaters or HVAC if included, and auxiliary-power alarm response | Contract boundary and observed response are clear |
Do not convert broad claims into acceptance criteria. For example, an online statement about fast switching, efficiency, or system safety can help identify a question, but the FAT should state the approved configuration, method, conditions, instrument, and acceptance limit. For a safety-architecture discussion that must be followed by model-specific evidence, see KRL’s battery-safety overview.
FAT Records and Shipment Release
An EPC buyer should not finish the FAT with a verbal conclusion. The release file should make a future audit possible without relying on the people who attended the test. It should include the approved procedure, the final configuration register, completed test forms, instrument traceability, photographs where useful, open-item log, deviation approvals, and signatures or electronic approvals from the authorized parties.
- Class A: shipment blocker—an item that affects safety, contracted function, identity, documentation, or required certification.
- Class B: controlled pre-shipment closure—an item that can close before packing when evidence and owner are defined.
- Class C: site-stage item—an item explicitly moved to SAT or commissioning with a test method, owner, date, and commercial boundary.
- No category: a verbal promise—do not treat it as closed until it is entered into the signed action register.
This classification protects both sides. It prevents the EPC buyer from withholding shipment over a site-only test, and it prevents the supplier from shipping a known factory nonconformity without an agreed remedy. The same discipline applies to delivery documentation. If the project includes overseas logistics, packaging and transport responsibility must be named rather than assumed. KRL’s experience in global C&I projects is relevant context in why global businesses choose KRL Power C&I systems, but each order still needs its own shipment and acceptance record.
FAT and Site Acceptance Responsibilities
FAT and SAT serve different purposes. FAT validates the manufactured configuration and agreed factory-test sequences. SAT confirms the installed system, local wiring, site safety arrangements, grid or generator behavior, communications, and actual operating environment. The most reliable projects define both before the factory test, so a factory limitation is not misread as a product failure and a site issue is not deferred indefinitely.
| Typically verified at FAT | Typically verified at SAT | Boundary to document |
|---|---|---|
| Production identity, controlled build, cabinet functions, local alarms, internal communications, and agreed simulated sequences | Site cabling, grounding, civil interfaces, utility requirements, generator behavior, SCADA integration, and actual load operation | Which party supplies test equipment, simulators, permits, personnel, and final acceptance sign-off |
| Factory records, shipment readiness, preservation, and packing evidence | Installation quality, energization, performance under site conditions, and handover training | Warranty start point, defect-notification route, and closure evidence |
For projects that combine solar, storage, diesel, or critical loads, the SAT plan should also define operating modes and command priority. These interfaces are often more important than a generic capacity comparison. Relevant application context appears in KRL’s industrial diesel-hybrid microgrid case and KRL’s EV-charging energy-storage case. Use cases are not substitutes for the acceptance schedule; they help EPC teams identify interfaces that need a project-level test.
Procurement Decision Before Shipment
A BESS FAT earns its value when it converts uncertainty into a controlled decision. The buyer is not looking for a flawless presentation. The buyer is looking for a traceable record that shows the exact system, confirms the agreed tests, identifies remaining risk, and assigns every action to a named owner. That evidence protects the EPC contractor, the owner, the supplier, and the commissioning team.
- Release the shipment when all shipment blockers pass and all remaining actions have documented owners and dates.
- Hold the shipment when configuration identity, safety function, required document applicability, or contractual test evidence remains unresolved.
- Move only defined site-stage items to SAT, with an agreed test method and commercial boundary.
- Request KRL technical clarification when the final quotation, SLD, product configuration, and FAT evidence do not align.
The buyer’s leverage is greatest before shipment, but the process should remain factual and fair. Use the same FAT template for every qualified supplier, require evidence that applies to the actual project, and score the response against the approved acceptance schedule. For wider project-design context, review KRL’s commercial energy-storage design guide and KRL’s C&I system-selection guide.