| Compatible conductor range | Must cover the required ferrule sizes; a broad professional range is typically 0.14–10 mm². | Check the tool marking, technical datasheet, and actual compatibility with the selected ferrule series. | 15% | Pass if all required sizes are covered |
| Ferrule standard compatibility | Suitable for insulated or non-insulated wire-end ferrules manufactured to the applicable DIN 46228 requirements. | Compare ferrule dimensions, conductor cross-section, sleeve length, and crimp profile with the tool specification. | 10% | Pass if profile and size match |
| Pull-out strength | No single pull-out value applies to every ferrule size. Results must be compared at the same conductor size, ferrule type, conductor material, and test speed. | Perform tensile testing on at least 10 samples per size; record minimum, average, and failure mode in newtons. | 25% | Select the tool with the strongest repeatable result |
| Crimp consistency | Crimps should be fully formed, centered, and free from cracks, loose strands, excessive deformation, or conductor damage. | Inspect 30 consecutive crimps across small, medium, and large ferrule sizes; measure crimp height where specified. | 15% | Pass with no visible defects |
| Insulation quality | The ferrule sleeve must remain intact and securely attached; the crimp must not cut, split, or loosen the insulation. | Use visual inspection and a retention check after crimping. If the tool is marketed for electrical safety work, verify the applicable insulated-tool rating separately. | 15% | Pass if sleeve and insulation remain undamaged |
| Calibration traceability | A current calibration record should identify the tool serial number, measurement uncertainty, calibration date, due date, and traceability to national or international standards. | Request a calibration certificate from an ISO/IEC 17025-accredited laboratory or an equivalent documented quality system. | 10% | Pass with complete traceable records |
| Calibration interval control | Use a risk-based interval; annual verification is a practical starting point for frequently used production tools. | Review usage frequency, overload history, failed inspections, and the organization’s documented calibration procedure. | 5% | Pass if interval is documented |
| Locking and release mechanism | The tool should complete the crimp cycle reliably and prevent premature release when the design requires a controlled full cycle. | Test the mechanism under repeated operation and confirm that incomplete crimps cannot be mistaken for completed crimps. | 3% | Pass if operation is repeatable |
| Ergonomics and maintenance | Low hand force, clear size markings, corrosion-resistant surfaces, replaceable wear parts, and accessible cleaning instructions. | Conduct an operator trial and review spare-part availability, lubrication requirements, and maintenance documentation. | 2% | Pass if suitable for planned workload |