CPRI Short Circuit Test Report
MS HDG Trefoil Cable Clamps
Short-time withstand current test on trefoil clamps for 49–60 mm dia. cables, conducted per IEC 61914 methodology. Tested at 10 kA rms / 3 s & 20 kA peak on 33kV XLPE armoured cables. No damage observed. Full 6-sheet report available for download.
Download Full Test Report (PDF)Report No. CPRIBLRSCLMISC23T0883 · 6 Sheets · Issued 28 December 2023
IEC 61914 — Cable Cleats for Electrical Installations
IEC 61914 is the international standard specifically for cable cleats (trefoil clamps, single-way clamps, and multiway clamps). Its core test is the short-time withstand current test — cables are mounted in trefoil formation on the cleats, fault current is applied, and the cleat must show no mechanical failure or visible damage. The test setup used by CPRI (trefoil formation, 5 m cleat spacing, nylon cable ties at 1 m intermediate span, fault current through 33kV XLPE cables) is consistent with IEC 61914 methodology.
Metro rail, power utilities, and large EPC contracts routinely require IEC 61914 compliance — a clamp that fails under fault current can allow cables to whip, contact each other, or pull away from supports, creating cascading faults and safety hazards.
This CPRI test confirms that KVP Electricals' MS HDG trefoil clamps withstand 10 kA rms for 3 seconds and 20 kA asymmetric peak with no damage — meeting the short circuit rating required on most 33kV metro projects.
Test Details
| Test Report Number | CPRIBLRSCLMISC23T0883 |
| Issued By | Central Power Research Institute (CPRI), Bengaluru |
| Report Date | 28 December 2023 |
| Date of Test | 20 June 2023 |
| Sample Tested | Trefoil Clamp (MS HDG) — for 49 to 60 mm dia. cable, with Nylon cable tie intermediate restrain |
| Test Type | Rated Short-Time Withstand Current |
| Customer Requirement | 10 kA rms for 3.0 s & 20 kA peak |
| Cable Used in Test | 3 × 1×300 sq.mm XLPE insulated 33 kV single-core aluminium armoured cables — trefoil formation |
| Clamp Spacing in Test | 5 m apart (with 4 nylon cable ties at 1 m span between clamps) |
* Test conducted per customer's specification. No published IS/IEC standard number was referenced — the test criteria were defined by KVP Electricals to match project tender requirements.
Test Results
| Peak Current (R-phase) | 21.71 kA |
| RMS Current (R) | 10.32 kA |
| RMS Current (Y) | 10.76 kA |
| RMS Current (B) | 10.46 kA |
| Duration | 3.20 seconds |
| Physical Inspection | ✓No visible damage to trefoil clamps or nylon ties |
| Overall Result | ✓COMPLIED — sample meets customer requirements |
Note on Standard / Specification in the Report
The CPRI report field "Standard / Specification" reads "Customer's instructions" rather than citing IEC 61914 by number. This is because KVP Electricals submitted the test parameters directly (10 kA rms, 3 s, 20 kA peak) as derived from the project tender specification — rather than referencing the standard number explicitly.
The test setup, methodology, and pass/fail criteria are fully aligned with IEC 61914:2015(Cable cleats — short-time withstand current test). CPRI's Short Circuit Laboratory is STL-accredited and is one of India's premier independent test facilities for electrical switchgear and accessories.
Download the Full Test Report
All 6 sheets including oscillogram reference, photographs, test circuit diagram, and manufacturer drawings — as issued by CPRI.
Download PDF — CPRIBLRSCLMISC23T0883Reproduced with complete set of sheets as permitted under CPRI publication guidelines.
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