tradvolt.com › Guides › CN→IN BMS Comm-Test (r14)
This page is a working process guide for the BMS communication-test stage of lithium-battery shipments moving on the China to India corridor. It maps the step sequence, document set, timeline and HS/duty handling around the test. Figures, duty rates and certificate availability are tracked as indicative or PENDING until the sources named in the footer are confirmed by muse-ba.
The BMS communication test is the bench-level check that the pack's battery management system responds correctly on the bus the inverter or charger expects (typically CAN 2.0B or RS-485) before the lot is sealed for the CN→IN leg. This guide treats the test as a maintenance step: it has an owner, an input, an output and a done-when condition. It is written for technical buyers, QA leads, and corridor coordinators who already operate within an ISO 9001 or IATF 16949 quality system.
The guide does not cover pack assembly, cell grading, UN 38.3 transport tests or customs clearance itself; those sit in adjacent guides in the r14 set. Where a referenced document, certificate or duty rate is not directly sourced on this page, the row carries the marker PENDING or UNCERTAIN and is queued for muse-ba.
| Step # | Action | Owner | Input document | Output document | Done-when |
|---|---|---|---|---|---|
| 1 | Confirm test scope and cell chemistry | Exporter QA lead | Purchase order line + cell chemistry tag (LFP/NMC) | Maintenance Scope Note (MSN-r14-BMS-01) | MSN signed and filed under the lot ID |
| 2 | Retrieve OEM BMS datasheet and protocol map | Exporter QA technician | OEM BMS datasheet, OEM protocol map (revision-stamped) | Stamped PDF copy in /datasheets/bms/ | Latest revision is on file and revision date ≤ 12 months |
| 3 | Run the bench communication test | Exporter QA technician | Bench rig, isolated DC supply, OEM cable harness | BMS Comm-Test Log (CTL-r14-BMS-02) | All slave IDs respond and frames are captured without bus errors |
| 4 | Compare frames against protocol map | Exporter QA engineer | BMS Comm-Test Log, OEM protocol map | Drift Note (DN-r14-BMS-03) if any | Drift Note is "none" or signed off with deviation code |
| 5 | Issue or block the BMS Comm-Test Certificate | Exporter QA lead | BMS Comm-Test Log + Drift Note | BMS Comm-Test Certificate (CTC-r14-BMS-04) — signed, or block tag | Certificate carries lot ID, signature, and date; or lot is blocked |
| 6 | Attach certificate to the corridor shipment file | Document controller | Signed BMS Comm-Test Certificate | Updated shipment folder /shipments/CN-IN/<lot>/ | Certificate appears in the shipment folder and is hash-pinned |
| 7 | Archive test artefacts in the BMS evidence folder | Document controller | Log, Drift Note, Certificate | Archive entry in BMS evidence index | Index row references all three artefacts by filename |
The following filenames must exist for every CN→IN lot that completes the BMS communication test. Names are literal so they can be enforced in the document management system:
MSN-r14-BMS-01_maintenance-scope-note.mdBMS-datasheet_oem-rev-stamped.pdf (stored under /datasheets/bms/)BMS-protocol-map_oem-rev-stamped.pdf (stored under /datasheets/bms/)CTL-r14-BMS-02_comm-test-log.csvDN-r14-BMS-03_drift-note.md (or DN-r14-BMS-03_none.md)CTC-r14-BMS-04_comm-test-certificate.pdf (signed)shipment-folder_CN-IN_<lot-id>/index.mdbms-evidence-index_r14.csvFilename enforcement is what allows a corridor auditor to reconstruct the chain later. A lot without all eight rows is treated as incomplete by this guide.
| Stage | Indicative days | Marker |
|---|---|---|
| Scope note signed (Step 1) | Day 0 | Fixed reference |
| Datasheet & protocol map on file (Step 2) | 0–1 | UNCERTAIN (OEM portal latency) |
| Bench test run (Step 3) | 1–2 | Indicative |
| Drift comparison (Step 4) | 2–3 | Indicative |
| Certificate signed or lot blocked (Step 5) | 3 | Indicative |
| Certificate attached to shipment file (Step 6) | 3–4 | Indicative |
| Archive entry created (Step 7) | 4–5 | Indicative |
The bench test, comparison and certificate stages are tightly coupled; the float sits in Steps 2 and 7, both of which depend on document systems outside the test rig.
| Cost slot | Basis | Value | Marker |
|---|---|---|---|
| QA lead time, scope & sign-off | Internal hours | Indicative | PENDING — internal rate card |
| Bench rig & isolated DC supply | Internal capex amortisation | Indicative | PENDING — internal rate card |
| OEM datasheet / protocol map access | OEM portal licence | Indicative | UNCERTAIN — OEM terms vary |
| Engineer frame-comparison time | Internal hours | Indicative | PENDING — internal rate card |
| Document control & archive | Internal hours | Indicative | PENDING — internal rate card |
| Re-test cost if lot is blocked | Rework hours + parts | Indicative | UNCERTAIN — depends on root cause |
This table contains slot rows only. No hard price is published on this page. Once muse-ba confirms internal rate cards and OEM licence terms, the slot values can be filled in.
| Field | Value | Marker |
|---|---|---|
| Indicative HS code (lithium-ion packs) | 8507.60 (lithium-ion accumulators, including separators) — confirm against the India Customs ICEGATE lookup | PENDING — confirm on ICEGATE |
| Indian Basic Customs Duty (BCD) | Rate pending lookup on the India Customs / CBIC page for the applicable year | PENDING |
| Integrated GST / compensation cess | Rate pending lookup on CBIC notifications for HS 8507.60 | PENDING |
| Social Welfare Surcharge / Additional Duty | Rate pending CBIC lookup | PENDING |
| China export-side rebate status | Status pending the China Customs / MOFCOM page for the shipment year | PENDING |
| BMS test certificate usage at Indian Customs | Used as supporting technical evidence; not a standalone clearance document | Fixed guidance |
Disclaimer. HS classification and duty rates for lithium battery packs moving on the CN→IN corridor are jurisdiction-specific and change with budget notifications. The rows above are placeholders pending direct lookup on the India Customs ICEGATE portal and CBIC notifications. The BMS communication-test certificate described in this guide supports technical compliance; it is not, on its own, a customs clearance document.
Use the button below to download the printable PDF version of the document checklist and step-sequence table. The download fires a download_checklist event into the dataLayer for downstream analytics.
Download the CN→IN BMS Comm-Test checklist (PDF)
Once the checklist is in hand, the next action for an active lot is to request a formal quote against the signed Maintenance Scope Note:
Most CN→IN packs are checked on CAN 2.0B at 250 or 500 kbit/s, with RS-485 / Modbus as a fallback. The exact bus is fixed by the OEM datasheet referenced in Step 2.
No. UN 38.3 is the UN transport-test certificate and is handled in a separate corridor guide. The BMS Comm-Test Certificate covers bench-level bus behaviour only.
The certificate is lot-specific and tied to the serial range recorded on it. It does not travel with the pack to a different lot.
The exporter QA lead signs the block tag, and the OEM is looped in for root-cause analysis. The document controller does not countersign a block.
It sits inside the document management system under the corridor release tag, in this case r14, and is referenced from bms-evidence-index_r14.csv.
Every factual sentence on this page is tied to a named source in the table below. Rows marked Internal point to this guide's own process artefacts rather than an external authority. muse-ba reviews all rows before publication.
| Claim | Source | File / section |
|---|---|---|
| BMS buses referenced (CAN 2.0B, RS-485/Modbus) are common on CN→IN packs | OEM BMS datasheets (e.g. manufacturer portals for Tier-1 BMS vendors) | /datasheets/bms/BMS-datasheet_oem-rev-stamped.pdf |
| UN 38.3 is the UN transport test, separate from bench comm-test | UN Recommendations on the Transport of Dangerous Goods, 38.3 section | Adjacent corridor guide (UN 38.3 r14) |
| HS 8507.60 covers lithium-ion accumulators | India Customs ICEGATE HS code lookup (lookup pending) | Section 6, ICEGATE row |
| BCD / IGST / SWS rates for HS 8507.60 | CBIC notifications, India (rate pending) | Section 6, CBIC rows |
| Step sequence and document set | Internal — tradvolt.com CN→IN corridor process (r14) | Sections 2 and 3 |
| Cost slots (hours, amortisation, OEM licence, rework) | Internal — tradvolt.com cost-template (rates pending) | Section 5 |
| Timeline (5-day indicative envelope) | Internal — tradvolt.com corridor SLA (r14) | Section 4 |
| download_checklist dataLayer event | Internal — tradvolt.com analytics spec | Section 7, anchor #cta-download |