IEC 62109-1 Figure D.3 Straight Unjointed Test Finger

IEC 62109-1 Figure D.3 Straight Unjointed Test Finger is a precision safety verification instrument engineered for photovoltaic (PV) inverter and power conversion equipment compliance testing. This specialized tool incorporates a rigid stainless steel probe that simulates human finger access patterns, enabling critical verification of hazardous live part inaccessibility in accordance with IEC 62109-1 safety standards. The instrument features an insulating nylon handle engineered for secure, non-slip operation during high-voltage equipment testing, applying a calibrated 10N thrust force to replicate real-world accidental contact scenarios.

Manufactured to exacting dimensional tolerances and material specifications, this test finger provides laboratories and quality control departments with reliable verification of PV equipment safety compliance. The instrument’s construction ensures dimensional stability under test conditions, delivering consistent performance for manufacturers requiring validation against IEC 62109-1, UL 62109-1, and related international safety standards for electrical equipment.

Technical Specifications:

• Probe Type: Straight Unjointed Test Finger (IEC 62109-1 Figure D.3 compliant for PV equipment verification)
• Finger Material: Stainless steel (rigid construction, corrosion-resistant, maintains dimensional accuracy under test conditions)
• Handle Material: Nylon (electrically insulating, heat-resistant, non-slip surface for secure grip during high-voltage equipment testing)
• Key Dimensions:
  • Finger Diameter: 12 mm ± 0.1 mm
  • Effective Finger Length: 80 mm ± 0.2 mm
  • Total Length (Finger + Handle): 180 mm ± 0.5 mm
  • Finger Tip Configuration: Hemispherical, radius 6 mm ± 0.05 mm (smooth surface to prevent enclosure damage during testing)
• Applied Thrust Force: 10N ± 0.5N (calibrated force application to simulate accidental human contact with PV equipment)
• Primary Function: Verification of hazardous live/high-voltage part inaccessibility in PV inverters and power converters per IEC 62109-1 and UL 62109-1 test procedures

Standardized Test Procedures:

1. Inspect the test finger for mechanical integrity (verify absence of bent steel components, cracked handle, or dimensional deviations) to ensure testing accuracy.
2. Power on the PV inverter/power converter and allow the equipment to reach normal operating mode.
3. Grip the insulating nylon handle and align the straight probe with equipment access openings (ventilation grilles, terminal covers, protective barriers).
4. Apply steady 10N thrust force to the probe toward internal hazardous components.
5. Verify whether the probe contacts any live/high-voltage components during force application.
6. Document test results to determine equipment compliance with IEC 62109-1 safety requirements.