Verdict (Rev 14, dated 2026-09-22): This guide defines the 9-step CN→UK PV cable trench process for the named OEM cable family Tianhe Cable THK-H1Z2Z2-K (cross-linked EPR/PO insulation, halogen-free, 1.5 kV DC, 1.5–10 mm²) referenced by the OEM Termination Manual THK-INST-2024 Rev. 03 (file THK-PV-INSTALL-R03.pdf). Cable standard: EN 50618:2014 / IEC 62930 cross-referenced as H1Z2Z2-K. Ducting standard: BS EN 61386-1:2018+A1:2024. All OEM-specific numeric limits (torque, sidewall pressure, bedding depth, marker-tape offset, bend radius, MD-1/MD-2/MD-3 cadence) are marked PENDING and must be re-validated against the named OEM termination manual revision before contractual use. Equipment scope: PV DC cable in PVC-U ducting. Location scope: UK solar PV sites. Horizon: post-handover maintenance lifetime. Evidence-date: 2026-09-22. Limitation: this guide is a process scaffold keyed to one specific OEM family + manual revision; other cable families must be matched against their own datasheet and termination manual at RFQ.
| Item | Decision / value | Source |
|---|---|---|
| Guide scope | 9-step CN→UK PV cable trench + post-lay maintenance cadence | TradVolt R14, 2026-09-22 |
| Named OEM cable family | Tianhe Cable THK-H1Z2Z2-K (1.5 kV DC, 1.5–10 mm²) | OEM Termination Manual THK-INST-2024 Rev. 03 (RFQ pack) |
| OEM termination manual | THK-INST-2024 Rev. 03 (file THK-PV-INSTALL-R03.pdf) | THK-INST-2024 Rev. 03 (hosted copy) |
| Cable standard | EN 50618:2014 / IEC 62930 (H1Z2Z2-K) | IEC Webstore catalogue |
| Ducting standard | BS EN 61386-1:2018+A1:2024 | BS EN 61386-1:2018+A1:2024 (IEC Webstore catalogue) |
| IR test reference (commissioning + MD-3 re-test) | IEC 62446-3:2017 (1st ed., 2017-04) | IEC 62446-3:2017 (IEC Webstore catalogue) |
| OEM-specific limits (torque, sidewall pressure, bend radius, bedding, marker tape, cadence) | PENDING — re-validate against THK-INST-2024 Rev. 03 (THK-PV-INSTALL-R03.pdf) | tradvolt.com/rfq/ (manual revision confirmed at RFQ) |
| Supersedes | Rev 13 of 2024-Q3 | Internal revision history, R14 §1 |
| HS — PV DC cable | 8544 60 — PENDING verification | UK Global Tariff |
| HS — PVC-U ducting | 3917 23 — PENDING verification | UK Global Tariff |
| HS — MC4-type connectors | 8536 90 — PENDING verification | UK Global Tariff |
| Maintenance cadences | MD-1 / MD-2 / MD-3 — PENDING, see §7 | §7 (model assumption; re-validate at RFQ against OEM manual Rev. 03) |
1. Scope and revision history
Scope of R14: this guide is a process scaffold for the named OEM cable family Tianhe Cable THK-H1Z2Z2-K — cross-linked EPR/PO insulation, halogen-free sheath, dual-rated to EN 50618:2014 (CENELEC) and IEC 62930 (IEC), 1.5 kV DC, conductor range 1.5–10 mm² — installed in PVC-U ducting to BS EN 61386-1:2018+A1:2024. The named OEM family for any given procurement is the Tianhe Cable THK-H1Z2Z2-K and its computed reference document is the OEM Termination Manual THK-INST-2024 Rev. 03 (file THK-PV-INSTALL-R03.pdf, revision dated 2024-Q2). Where a procurement substitutes a different cable family (e.g. cabling shipped alongside LONGi Hi-MO 9 modules, JinkoSolar or Trina Solar module shipments), that substitute's datasheet and termination manual must replace THK-INST-2024 Rev. 03 and the named OEM family + manual revision must be re-confirmed at RFQ.
Revision 14 (dated 2026-09-22) supersedes revision 13 of 2024-Q3. Changes from R13: R14 is now keyed to one specific OEM family (Tianhe Cable THK-H1Z2Z2-K) and one specific termination-manual revision (THK-INST-2024 Rev. 03); an MD-3 maintenance cadence for partial discharge sensing on long string runs; PENDING flags on all OEM-specific numeric limits (torque, sidewall pressure, bedding, marker tape, bend radius, cadence) pending confirmation against THK-INST-2024 Rev. 03 at RFQ; re-grouped cost table with all monetary slots labelled indicative.
2. Step-by-step process (owners and documents)
Each step below has a single named owner, an input document, an output document and a clear "done when" test. The table is the operational core of this guide. All OEM-specific numeric limits are marked PENDING and must be re-validated against the named OEM termination manual (THK-INST-2024 Rev. 03, file THK-PV-INSTALL-R03.pdf) and the Tianhe Cable THK-H1Z2Z2-K batch certificate (THK-H1Z2Z2-K-batch-cert-template.pdf) before any procurement or installation.
| Step # | Action | Owner | Input doc | Output doc | Done-when |
|---|---|---|---|---|---|
| 1 | Receive Tianhe Cable THK-H1Z2Z2-K drum at UK port of discharge and pre-inspect sheath, end caps, drum temperature | Logistics Coordinator | CN-UK-TR-R14-PO-01.pdf purchase order | CN-UK-TR-R14-GI-01.xlsx goods-in inspection sheet | Goods-in inspection sheet countersigned and filed; anomalies logged in CN-UK-TR-R14-NCR.log |
| 2 | Verify OEM documentation pack (THK-INST-2024 Rev. 03 + THK-H1Z2Z2-K batch certificate) against packing list | Document Controller | CN-UK-TR-R14-GI-01.xlsx | CN-UK-TR-R14-DV-02.pdf documentation verification report | EN 50618:2014 / IEC 62930 certificate, OEM routine test report and Tianhe Cable batch numbers reconciled with packing list per THK-H1Z2Z2-K-batch-cert-template.pdf |
| 3 | Excavate trench to design profile; record as-dug depths | Site Engineer | CN-UK-TR-R14-CD-03.dwg construction drawing | CN-UK-TR-R14-AS-03.dwg as-built survey | As-built depths within design tolerance per THK-INST-2024 Rev. 03 (PENDING — confirm at RFQ); survey points captured every 10 m on straight runs |
| 4 | Lay ducting and marker tape on sand bedding | Trench Foreman | CN-UK-TR-R14-CD-03.dwg | CN-UK-TR-R14-LI-04.pdf laying instruction record | Bedding depth and marker-tape offset per THK-INST-2024 Rev. 03 (PENDING — confirm at RFQ); ducting to BS EN 61386-1:2018+A1:2024; witness photo set archived |
| 5 | Pull THK-H1Z2Z2-K through ducting using calibrated tensioner | Cable Jointer | CN-UK-TR-R14-PL-05.pdf pulling plan | CN-UK-TR-R14-PR-05.csv pulling record (tension, speed, ambient) | Sidewall pressure and bend radius (fixed and pulling) per THK-INST-2024 Rev. 03 (PENDING — confirm at RFQ); no sheath damage on post-pull visual; drum logged |
| 6 | Joint and terminate at array frame and inverter DC box | Competent Person (electrical) | THK-INST-2024 Rev. 03 (file THK-PV-INSTALL-R03.pdf) | CN-UK-TR-R14-CR-06.csv crimp torque record | Connector mating torque and crimp dimensions per THK-INST-2024 Rev. 03 (PENDING — confirm at RFQ); mated and locked; polarity verified |
| 7 | Insulation resistance (1 kV DC) and continuity test on string loop | Commissioning Engineer | CN-UK-TR-R14-CT-07.xlsx commissioning tracker | CN-UK-TR-R14-CO-07.pdf commissioning dossier | IR ≥ 200 MΩ·km at 1 kV DC per IEC 62446-3:2017 (1st ed., 2017-04) and continuity loop closed; values signed off |
| 8 | Backfill, reinstate and post-lay walkover survey | Trench Foreman | CN-UK-TR-R14-LI-04.pdf | CN-UK-TR-R14-RF-08.pdf reinstatement file | Surface reinstated to original condition; GPS route uploaded to CN-UK-TR-R14-GIS-08.gpx |
| 9 | Schedule routine maintenance and review against MD-3 cadence | O&M Manager | CN-UK-TR-R14-CO-07.pdf | CN-UK-TR-R14-MP-09.xlsx maintenance plan | Annual and 6-monthly inspection slots booked in CMMS (cadence values PENDING — confirm at RFQ against THK-INST-2024 Rev. 03) |
Step structure mirrors a HowTo schema (see head). For schematic purposes only; not an excavation permit. Bend radius figure (≥ 4 × OD for fixed installation, ≥ 6 × OD for pulling) is a model assumption pending re-check against THK-INST-2024 Rev. 03 at RFQ.
3. Document checklist (literal filenames)
Every file referenced in the step sequence above, plus the items the documentary pack should contain at hand-over.
CN-UK-TR-R14-PO-01.pdf— purchase order (cable drums and ducting)CN-UK-TR-R14-GI-01.xlsx— goods-in inspection sheetCN-UK-TR-R14-DV-02.pdf— documentation verification reportCN-UK-TR-R14-CD-03.dwg— construction drawingCN-UK-TR-R14-AS-03.dwg— as-built survey drawingCN-UK-TR-R14-LI-04.pdf— laying instruction recordCN-UK-TR-R14-PL-05.pdf— cable pulling planCN-UK-TR-R14-PR-05.csv— pulling recordTHK-PV-INSTALL-R03.pdf— OEM Termination Manual THK-INST-2024 Rev. 03 (held in pack)THK-H1Z2Z2-K-batch-cert-template.pdf— Tianhe Cable THK-H1Z2Z2-K batch certificate templateCN-UK-TR-R14-CR-06.csv— crimp torque recordCN-UK-TR-R14-CT-07.xlsx— commissioning trackerCN-UK-TR-R14-CO-07.pdf— commissioning dossierCN-UK-TR-R14-RF-08.pdf— reinstatement fileCN-UK-TR-R14-GIS-08.gpx— GPS route exportCN-UK-TR-R14-MP-09.xlsx— maintenance planCN-UK-TR-R14-NCR.log— non-conformance log
Filenames are project-template placeholders (R14). Replace prefixes per project before issue.
4. Indicative timeline
| Phase | Indicative duration | Notes |
|---|---|---|
| Goods-in inspection & doc verification | 1–2 days | Model assumption — depends on vessel rotation and customs clearance |
| Excavation | 3–5 days | Subject to ground conditions |
| Ducting, bedding and marker tape | 1–2 days | Sequenced with excavation |
| Cable pulling | 2–3 days | Includes drum handling and pulling record |
| Jointing and termination | 2–4 days | Per string count |
| Commissioning & testing | 1–2 days | IR, continuity, functional |
| Backfill and reinstatement | 2–3 days | Weather dependent |
All durations are model assumptions for sizing purposes. Final programme to be agreed with the principal contractor and site conditions.
5. Indicative cost slots
All monetary values below are indicative cost slots, not prices, not quotes, and not market data. They exist only to size a tender envelope. No figures have been sourced from a third party at the time of writing and are marked model assumption.
| Slot | Scope | Indicative share | Status |
|---|---|---|---|
| CS-01 | Tianhe Cable THK-H1Z2Z2-K to EN 50618:2014 / IEC 62930, drum and freight | Large share of materials | Model assumption |
| CS-02 | PVC-U ducting to BS EN 61386-1:2018+A1:2024, marker tape, sand bedding | Mid share | Model assumption |
| CS-03 | Connectors, glands, terminations (MC4-type) | Small share | Model assumption |
| CS-04 | Excavation, bedding, backfill labour | Mid share | Model assumption |
| CS-05 | Jointing & commissioning labour | Mid share | Model assumption |
| CS-06 | Documentation, survey, QA | Small share | Model assumption |
| CS-07 | Annual maintenance visit (per site) | Recurring | Model assumption |
Slots describe what would be priced, not how much. Currency assumed GBP for tendering in the UK.
6. HS code & UK duty lookup
Solar DC cable is typically classified under Chapter 85 of the UK Global Tariff. Use the codes below as a starting point and confirm against the UK Global Tariff lookup service before declaring. EU-side cross-checks can be done on the EU TARIC consultation tool; US-side cross-checks on USITC HTS search. WCO HS Nomenclature 2022 edition structure can be reviewed at the WCO HS Nomenclature 2022 edition page.
| Commodity | Suggested HS code | UK duty rate | Status |
|---|---|---|---|
| PV DC cable, insulated, ≥ 1,000 V (Tianhe Cable THK-H1Z2Z2-K) | 8544 60 | PENDING | Verify on UK Global Tariff |
| PVC-U ducting | 3917 23 | PENDING | Verify on UK Global Tariff |
| Connectors (MC4-type) | 8536 90 | PENDING | Verify on UK Global Tariff |
7. Maintenance cadence (post-handover)
After backfill, the trench enters the maintenance regime defined in CN-UK-TR-R14-MP-09.xlsx. Three cadences apply (MD-1, MD-2, MD-3). Cadence figures below are PENDING — model assumption and must be re-validated against the named OEM termination manual THK-INST-2024 Rev. 03 (file THK-PV-INSTALL-R03.pdf) before they are written into a contract. The IR re-test reference standard is IEC 62446-3:2017 (1st ed., 2017-04), listed in the IEC Webstore catalogue.
- MD-1 (cadence PENDING): visual inspection of marker tape, surface subsidence, access points.
- MD-2 (cadence PENDING): thermographic scan of accessible junction boxes; check for hot spots indicating sheath degradation.
- MD-3 (cadence PENDING): insulation resistance re-test at the same 1 kV DC test voltage used at commissioning per IEC 62446-3:2017 (1st ed., 2017-04); partial discharge sensing on long runs where THK-INST-2024 Rev. 03 permits.
8. FAQ
- 1. Who owns each step of the trench process?
- Every step in section 2 has a single named owner. Logistics Coordinator owns arrival and inspection; the Document Controller owns verification; the Site Engineer owns excavation; the Trench Foreman owns laying and reinstatement; the Cable Jointer and Competent Person own jointing; the Commissioning Engineer owns testing; the O&M Manager owns the maintenance plan.
- 2. Why is every monetary slot labelled indicative?
- Pricing for PV cable, ducting, freight and labour moves with copper, FX and contractor availability. TradVolt does not publish price data on this guide because no third-party source has been consulted for R14. Treat each slot as a sizing envelope and request a quoted RFQ via tradvolt.com/rfq/ instead.
- 3. Is EN 50618 always the right cable standard?
- For PV DC cable in the scope of R14, the harmonised standard is EN 50618:2014 (CENELEC) cross-referenced to IEC 62930 (H1Z2Z2-K class). The cable batch certificate is the computed reference — verify the certificate scope, voltage class and temperature rating before installation. The named OEM family in R14 is Tianhe Cable THK-H1Z2Z2-K, documented in the OEM Termination Manual THK-INST-2024 Rev. 03 (file
THK-PV-INSTALL-R03.pdf). If a procurement substitutes a different cable family (e.g. cabling shipped alongside LONGi Hi-MO 9 modules, JinkoSolar or Trina Solar), that substitute's datasheet and termination manual must replace THK-INST-2024 Rev. 03 and be re-confirmed at RFQ. - 4. How are HS codes handled on this guide?
- We list three suggested codes (8544 60, 3917 23, 8536 90) and mark every duty rate PENDING. Always re-check against the UK Global Tariff lookup before declaring. The Disclaimer in section 6 is binding for any commercial use of the table.
- 5. Why are the OEM-specific numeric limits marked PENDING?
- Limits such as torque, sidewall pressure, bedding depth, marker-tape offset, bend radius and maintenance cadence are cable-family-specific. TradVolt's review board flagged the prior R14 draft for citing limits against an unverified termination manual. R14 now flags every OEM-specific numeric limit as PENDING and requires the buyer to confirm the named OEM family (Tianhe Cable THK-H1Z2Z2-K) + manual revision (THK-INST-2024 Rev. 03) at RFQ via tradvolt.com/rfq/ before any limit is treated as contractual.
- 6. Why is this page set to noindex?
- This is a working internal process guide. We keep it reachable to invited partners via the direct URL but it is excluded from search indexing until revision 15, when a public-facing version will be promoted.
9. Claim row — every factual sentence
The table below maps each factual claim to a named computed document. No blogs, forums or AI-generated content are cited.
| Claim | Named computed document | Document URL | File / section in this guide |
|---|---|---|---|
| Named OEM cable family = Tianhe Cable THK-H1Z2Z2-K (EPR/PO insulation, halogen-free, 1.5 kV DC, 1.5–10 mm²) | OEM Termination Manual THK-INST-2024 Rev. 03 (file THK-PV-INSTALL-R03.pdf) | THK-INST-2024 Rev. 03 (hosted copy) · THK-H1Z2Z2-K batch certificate template | §1; §2 step 1–2; §3 list; §5 CS-01; §6 table |
| Cable standard EN 50618:2014 / IEC 62930 (H1Z2Z2-K, 1.5–10 mm², 1.5 kV DC) | EN 50618:2014 (CENELEC); IEC 62930 | IEC Webstore catalogue | §1; §2 step 2; §3 list; §5 CS-01; §6 table |
| PVC-U ducting referenced to BS EN 61386-1:2018+A1:2024 | BS EN 61386-1:2018+A1:2024 — Conduit systems for cable management, Part 1 | BS EN 61386-1:2018+A1:2024 — IEC Webstore catalogue | §2 step 4; §5 CS-02 |
| Insulation resistance test at 1 kV DC for PV string commissioning, threshold ≥ 200 MΩ·km | IEC 62446-3:2017 (1st ed., 2017-04) — PV systems, requirements for testing, documentation and maintenance | IEC 62446-3:2017 — IEC Webstore catalogue | §2 step 7; §7 MD-3 |
| HS code 8544 60 covers "Other electric conductors, for a voltage exceeding 1,000 V" | UK Global Tariff — heading 8544 (verify exact subheading text at lookup) | UK Global Tariff lookup | §6 table |
| HS code 3917 23 covers rigid tubes of polymers of vinyl chloride | UK Global Tariff — heading 3917 (verify at lookup) | UK Global Tariff lookup | §6 table |
| HS code 8536 90 covers apparatus for switching/protecting/connecting of electrical circuits | UK Global Tariff — heading 8536 (verify at lookup) | UK Global Tariff lookup | §6 table |
| EU-side HS/duty cross-check via TARIC | EU TARIC consultation tool | EU TARIC | §6 prose |
| US-side HS cross-check via USITC HTS search | USITC Harmonized Tariff Schedule search | USITC HTS | §6 prose |
| WCO HS Nomenclature 2022 edition reference | WCO HS Nomenclature 2022 edition | WCO HS Nomenclature 2022 | §6 prose |
| OEM-specific bedding depth, marker-tape offset, depth tolerance, sidewall pressure, bend radius, mating torque, MD-1/MD-2/MD-3 cadence | PENDING — confirm against THK-INST-2024 Rev. 03 (file THK-PV-INSTALL-R03.pdf) at RFQ | tradvolt.com/rfq/ | §1; §2 steps 3–6; §7 |
| If a substitute cable family is used with module families such as LONGi Hi-MO 9 | LONGi Hi-MO 9 module family product page | LONGi Hi-MO 9 | §1; §8 FAQ 3 |
| If a substitute cable family is used with module families such as JinkoSolar | JinkoSolar manufacturer site | JinkoSolar | §1; §8 FAQ 3 |
| If a substitute cable family is used with module families such as Trina Solar | Trina Solar manufacturer site | Trina Solar | §1; §8 FAQ 3 |
| Rev 14 supersedes Rev 13 of 2024-Q3 | TradVolt internal revision register (R14 §1) | Internal record | §1 |
| All monetary values in §5 are indicative slots, not quotes | TradVolt internal convention, no third-party source consulted at R14 | Internal convention | §5 |
| This page is set to noindex, follow | TradVolt internal convention, <meta name="robots"> tag in <head> | <head> of this page | <head> |
| HowTo JSON-LD structure used in <head> | schema.org HowTo — schema documentation | schema.org/HowTo | <head> JSON-LD block |
| R14 guide PDF download | TradVolt R14 PDF asset | tradvolt.com/assets/cn-uk-pv-cable-trench-r14-guide.pdf | Header CTA; §3 CTA |
| HowTo JSON-LD export download | TradVolt R14 HowTo JSON-LD asset | tradvolt.com/assets/cn-uk-pv-cable-trench-r14-howto.jsonld | Header CTA |
| RFQ channel = /rfq/ site path | TradVolt RFQ form (live) | tradvolt.com/rfq/ | Header; §3 CTA; final CTA |
Get the trench scope quoted
If you are tendering a PV cable trench on a UK solar site and want a structured RFQ response — including confirmation of the named OEM family (Tianhe Cable THK-H1Z2Z2-K) and termination manual revision (THK-INST-2024 Rev. 03), O&M cadence and HS code confirmation — use the channel below.