Overview
IEC TS 62916:2017 specifies a reproducible test and analysis method for assessing the electrostatic discharge (ESD) susceptibility of discrete bypass diodes used in photovoltaic (PV) modules. The Technical Specification defines a progressive contact-discharge test (following the IEC 61000-4-2 model) and a statistical data‑analysis procedure based on the two‑parameter Weibull distribution to characterize diode surge‑voltage tolerance. It is intended to support qualification, incoming quality control and identification of ESD control needs during manufacturing, packaging, transportation and installation of PV modules.
Key Topics and Requirements
- Scope & limitations
- Tests discrete bypass diodes outside the module/junction box.
- Does not set pass/fail ESD levels or address large energy events (e.g., lightning).
- Sampling
- Ten unconditioned, identical diodes per test (same type, date code and factory recommended).
- Lead trimming/forming should be done prior to testing.
- Test equipment & setup
- Uses IEC 61000-4-2 contact discharge method (ESD gun with internal impedance 330 Ω, 150 pF).
- Grounding block to hold DUTs; anode grounded, cathode exposed.
- Positive polarity single‑surge mode; incremental voltage steps of 5 kV from 5 kV to a recommended capability of 30 kV (or higher).
- Test method
- Verify diode operation (multimeter diode-check) before testing.
- Apply progressive contact discharges to each diode; record environmental conditions (e.g., 20 °C ±5 °C, 50 % ±10 % RH recommended).
- Allow surge relaxation time for thermal stabilization if needed.
- Data analysis
- Analyze voltage-to-failure using the two‑parameter Weibull distribution.
- Use recommended median‑rank estimation and least‑squares linear regression form for extrapolation and reporting.
Applications
- Qualification of new bypass diode designs for PV modules.
- Incoming material quality control for diode suppliers.
- Root-cause analysis of production line quality excursions attributed to ESD-induced diode failures.
- Determining whether additional ESD handling controls are required in manufacturing, storage or installation workflows.
Who Should Use This Standard
- PV module manufacturers and assembly engineers
- Semiconductor and diode suppliers for PV applications
- Test labs performing ESD immunity characterization
- Quality, reliability and production engineers in the solar industry
Related Standards
- IEC 61000-4-2 - Electromagnetic compatibility (EMC) - ESD immunity test (referenced for test generator and contact‑discharge method)
- IEC TS 62916 references IEC TS 61836 for terms/definitions used in PV standards
Keywords: IEC TS 62916, bypass diode, electrostatic discharge, ESD susceptibility testing, photovoltaic modules, Weibull distribution, surge voltage tolerance, IEC 61000-4-2, PV quality control.