Standard Operating Procedure · Vertical: LFP (Lithium Iron Phosphate) Energy Storage + PV Modules · Issued by TradVolt OÜ · Evidence-date: 2026-09-22
| Item | Value | Source / status |
|---|---|---|
| Module model (computed) | Trina Solar TSM-NEG19RC.05 (Vertex N) | Trina product page (exact datasheet at RFQ) |
| Connector family | Stäubli MC4 / MC4-Evo 2 | Stäubli MA213 assembly instructions (rev. 2022-08) |
| Pass torque band | 2.0 Nm ± 0.2 Nm (cable gland nut) | Stäubli MA213 rev. 2022-08 — model assumption until RFQ confirms |
| AQL level | 1.0 major / 2.5 minor, Level II | ISO 2859-1:1999 |
| CN→LT target window | 34–45 days | TradVolt corridor log 2024–2025 |
| Discharge port | Klaipėda, LT | Fixed corridor scope |
Applies to framed PV modules fitted with factory-installed Stäubli MC4 / MC4-Evo 2 DC connectors (positive and negative leads) on Trina Solar TSM-NEG19RC.05 (Vertex N) modules, sourced from OEM facilities in China and discharged at Klaipėda, LT. Torque verification is performed on the cable gland nut of the male and female connector pair, not on module-to-rail clamps. The connector reference is the Stäubli MC4 / MC4-Evo 2 Assembly Instructions MA213 rev. 2022-08; the module reference is the Trina Solar TSM-NEG19RC.05 product datasheet (Vertex N series).
| Step # | Action | Owner | Input doc | Output doc | Done-when |
|---|---|---|---|---|---|
| 1 | Receive shipping file (PO, packing list, OEM torque sheet for Stäubli MC4 / MC4-Evo 2 on Trina TSM-NEG19RC.05) and confirm audit scope with buyer | TradVolt Order Desk | Buyer PO, OEM torque datasheet | TV-AUDIT-INT-001 internal intake form | Scope signed off by buyer email |
| 2 | Confirm Incoterms® 2020 term (e.g. FOB Shanghai / CIF Klaipėda), allocate risk per ICC rules, and validate HS classification against TARIC | TradVolt Trade Compliance | PO, commercial invoice draft | TV-COMPL-002 compliance memo | Incoterms code and HS code locked |
| 3 | Notify OEM of pre-shipment torque audit; align on witness window at the production line for Trina TSM-NEG19RC.05 | TradVolt China Sourcing Office | OEM contact, production plan | TV-CN-003 audit request notice | OEM confirms production line and date |
| 4 | Draw sample using ISO 2859-1 AQL; lot size = pallet quantity; AQL 1.0 inspection level II for connectors | TradVolt QA Inspector (CN) | Packing list, lot size | TV-QA-004 AQL sample sheet | Sample size recorded with justification |
| 5 | Measure torque on sampled Stäubli MC4 / MC4-Evo 2 male/female pairs using calibrated digital torque wrench; compare against the OEM-specified 2.0 Nm ± 0.2 Nm band per Stäubli MA213 rev. 2022-08 | TradVolt QA Inspector (CN) | Calibrated wrench, OEM torque spec | TV-QA-005 torque measurement log | Each reading logged with Nm and pass/fail |
| 6 | Record any deviation > ±0.2 Nm from the Stäubli 2.0 Nm specification and note connector batch/lot | TradVolt QA Inspector (CN) | TV-QA-005 | TV-QA-006 deviation register | All deviations listed by batch |
| 7 | Acceptance decision: PASS if all sampled connectors measure within 2.0 Nm ± 0.2 Nm and ISO 2859-1 AQL critical threshold is met; REJECT if acceptance number exceeded | TradVolt QA Lead | TV-QA-005, TV-QA-006 | TV-QA-007 pass/fail decision | Decision countersigned by OEM rep |
| 8 | Load container, seal, and complete CN export clearance via the PRC General Administration of Customs | Freight Forwarder + TradVolt China Office | Commercial invoice, packing list, customs declaration | CN export clearance receipt | Container sealed and customs-released |
| 9 | Sea freight CN port (Shanghai / Ningbo / Shenzhen) → Klaipėda under FIATA Multimodal Transport Document (FBL) | Freight Forwarder | FIATA FBL/BL | Onboard BL | Vessel departs CN port |
| 10 | LT import clearance at Klaipėda; HS code declared via TARIC lookup, duties/taxes posted, release granted | LT Customs Broker | BL, commercial invoice, packing list | LT customs release note | Container released for collection |
| 11 | Arrival audit at TradVolt Klaipėda hub: spot-check torque on 10 randomly drawn Stäubli MC4 / MC4-Evo 2 connectors from the received lot | TradVolt QA Inspector (LT) | Calibrated wrench, TV-QA-005 | TV-QA-011 arrival audit log | Spot-check readings filed |
| 12 | Compile final audit report, archive torque logs, and hand file to buyer | TradVolt Order Desk | TV-QA-007, TV-QA-011 | TV-AUDIT-FINAL-012 PDF report | Report delivered to buyer within 48 h of arrival |
Each sampled Stäubli MC4 / MC4-Evo 2 connector pair fitted to Trina Solar TSM-NEG19RC.05 modules is torqued to the OEM-specified value published in Stäubli Assembly Instructions MA213 rev. 2022-08: 2.0 Nm ± 0.2 Nm for the cable gland nut. A reading within this band is recorded as PASS on TV-QA-005. Any reading outside the band is recorded as FAIL on TV-QA-006.
[Claim: Tightening torque 2.0 Nm ± 0.2 Nm for MC4 / MC4-Evo 2 cable gland nut | Src: Stäubli MC4 / MC4-Evo 2 Assembly Instructions MA213 rev. 2022-08 | URL: https://www.staubli.com/global/en/electrical-connectors/products/mc4.html | accessed 2026-09-22 — model assumption until confirmed at RFQ against lot-specific datasheet]
[Claim: Connector safety design and test methods are governed by IEC 62852:2014+AMD1:2020 | Src: IEC 62852 catalogue entry | URL: https://webstore.iec.ch/en/products/?q=62852 | accessed 2026-09-22]
[Claim: Connectors for PV systems are evaluated to UL 61730-1:2022 (Module Safety Qualification, Part 1) | Src: UL 61730-1 | URL: https://www.shopulstandards.com/ProductDetail.aspx?productId=UL61730-1 | accessed 2026-09-22]
[Claim: Sample size and acceptance number derived from ISO 2859-1:1999 AQL tables | Src: ISO 2859-1:1999 | URL: https://www.iso.org/search.html?q=2859 | accessed 2026-09-22]
[Claim: Trina Vertex N module family includes the TSM-NEG19RC.05 (bifacial mono-crystalline) | Src: Trina Solar Vertex N product page | URL: https://www.trinasolar.com/en-glb/product/vertex-n-plus | accessed 2026-09-22 — module datasheet confirmed at RFQ]
Lot = pallet (modules fitted with Stäubli MC4 / MC4-Evo 2). Inspection level = General Inspection Level II per ISO 2859-1:1999. AQL = 1.0 for major defects (incorrect torque, damaged thread, cracked housing), AQL = 2.5 for minor defects (cosmetic). Sample size code letter and acceptance number (Ac) / rejection number (Re) are taken from the ISO 2859-1 tables at the time of audit; both numbers are written into TV-QA-004.
Digital torque wrench covering 0.5–5.0 Nm (covering the Stäubli 2.0 Nm target), calibrated within the previous 12 months. Calibration certificate reference is recorded on TV-QA-005. A backup mechanical wrench is kept in the QA kit.
| Leg | Mode | Typical duration | Dependency | Owner |
|---|---|---|---|---|
| OEM plant → CN port (Shanghai / Ningbo / Shenzhen) | Road | 2–4 days | Pre-shipment audit signed off (Step 7) | Freight Forwarder |
| CN export clearance | Customs | 1–2 working days | Commercial invoice, packing list, customs declaration | Freight Forwarder + TradVolt China Office |
| CN port → Klaipėda | Sea (FCL) | 30–38 days | Vessel schedule, FIATA FBL issued | Shipping Line |
| LT import clearance (Klaipėda) | Customs | 1–3 working days | BL, invoice, packing list, TARIC-based declaration | LT Customs Broker |
| Klaipėda port → TradVolt hub | Road / rail | 1 day | Customs release note (Step 10) | TradVolt Klaipėda Logistics |
| Total CN→LT window | Multimodal | 34–45 days | All Steps 1–11 closed | TradVolt OÜ |
[Claim: Corridor transit times based on TradVolt operational data for FCL sailings CN → Klaipėda | Src: TradVolt internal corridor log 2024-2025 | accessed 2026-09-22]
[Claim: Incoterms 2020 defines risk transfer and cost allocation between buyer and seller | Src: ICC Incoterms® 2020 | URL: https://iccwbo.org/business-solutions/incoterms-rules/incoterms-2020/ | accessed 2026-09-22]
[Claim: The FIATA Multimodal Transport Document (FBL) is the standard negotiable MT document for combined transport | Src: FIATA documents index | URL: https://fiata.org/ | accessed 2026-09-22]
[Claim: CN export clearance is filed through the official PRC customs portal (English) | Src: PRC General Administration of Customs | URL: http://english.customs.gov.cn/ | accessed 2026-09-22]
[Claim: LT import clearance uses the EU TARIC consultation tool | Src: European Commission TARIC | URL: https://ec.europa.eu/taxation_customs/dds2/taric/taric_consultation.jsp?Lang=en | accessed 2026-09-22]
All cost figures in this section are indicative and depend on container size, fuel surcharge, peak-season premium, and current duty/tax postings in TARIC. They are UNCERTAIN until a specific PO is quoted.
| Cost item | Basis | Status |
|---|---|---|
| Pre-shipment torque audit (Steps 1–7) | Per man-day, CN, inclusive of calibrated wrench | indicative |
| Sea freight CN → Klaipėda (FCL 40' HC) | Per container, subject to Bunker Adjustment Factor | indicative · UNCERTAIN |
| CN export clearance fees | Per shipment, set by forwarder | indicative · UNCERTAIN |
| LT import duties and VAT | Calculated against declared CIF and current TARIC postings | indicative · UNCERTAIN |
| Arrival audit at TradVolt hub (Step 11) | Per lot, inclusive of spot-check torque log | indicative |
HS code for framed PV modules (Trina TSM-NEG19RC.05) with mounted Stäubli MC4 / MC4-Evo 2 DC connectors: PENDING — lookup against the current EU TARIC query result and the PRC customs tariff schedule before each shipment.
EU import duty rate: PENDING — lookup at the time of quotation via the EU TARIC consultation tool (https://ec.europa.eu/taxation_customs/dds2/taric/taric_consultation.jsp?Lang=en).
VAT rate (LT): PENDING — lookup at the time of quotation against the current Lithuanian VAT schedule.
Official portals consulted:
Disclaimer: HS classification and duty/VAT rates are not hardcoded here because they depend on the exact panel model, wattage class, declared use (grid-tied vs. storage-coupled), and current TARIC postings. TradVolt re-verifies all of the above on every quote. No rate in this SOP is binding.
The following files are produced or received during the audit. Literal filenames are listed for buyer reference:
TV-AUDIT-INT-001_intake_form.pdfTV-COMPL-002_compliance_memo.pdfTV-CN-003_audit_request_notice.pdfTV-QA-004_AQL_sample_sheet.xlsxTV-QA-005_torque_measurement_log.xlsxTV-QA-006_deviation_register.xlsxTV-QA-007_pass_fail_decision.pdfCN_export_clearance_receipt.pdfFIATA_FBL_multimodal_BL.pdfLT_customs_release_note.pdfTV-QA-011_arrival_audit_log.xlsxTV-AUDIT-FINAL-012_report.pdfOEM_torque_datasheet_buyer_supplied.pdf (Stäubli MA213 rev. 2022-08 + Trina TSM-NEG19RC.05 datasheet)torque_wrench_calibration_certificate.pdfDocuments cited in this SOP are listed for buyer reference. To request a downloadable PDF copy of the TradVolt SOP, use the RFQ form in Section 12.
Send your module OEM, connector family, expected lot size, target CN port, and Incoterms® 2020 code. TradVolt replies within 48 working hours with a fixed quote covering Steps 1–12 above. Scope reference: Stäubli MC4 / MC4-Evo 2 on Trina TSM-NEG19RC.05 modules, CN→LT corridor, 34–45 day window.
Request Quote — replies in 48h
Owner: TradVolt OÜ, Tallinn / Klaipėda. Reviewed annually. Evidence-date: 2026-09-22. Last review date: 2026-09-22. Next review: 2027-09-22.