Junction Box Connectors: Task Group 10

Task Group 10 focuses on durability issues related to photovoltaic (PV) junction-box connectors, including both manufacturing and deployment issues. It will examine evidence for and initiate tests on durability and reliability of contacts, and susceptibility to mechanical or corrosive failure mechanisms.

Plastic wall materials need to retain their strength against ultraviolet (UV) exposure. The connectors should keep the joints rigid and interior sealed to humidity and dust, and protect the connector joints against reasonable external mechanical forces during installation and use. Standards and procedures are needed at the times of manufacture, installation, and for field repair/retrofit of connectors.

Progress Update

Task Group 10 has conducted a survey to prioritize efforts, reviewed standards already in place for their applicability to durability studies and is now working through a design failure mode and effect analysis to identify the most critical failure mechanisms.

Field failures are being sent to Mike Kempe at the National Renewable Energy Laboratory (NREL) for failure analysis. His lab is able to complete a computer-aided X-ray tomography scan (computerized tomography [CT] scan) of these samples. The CT scan provides high-quality images of a failed connector that help determine the root cause of the failure. If samples continue to show similar failure modes, the team will need to ensure there are standardized tests to address the issue. The International PV Quality Assurance Task Force is asking industry to submit field failures of PV connectors/cable to NREL for further analysis.

Intermateability of PV connectors from different manufacturers has been a reoccurring topic within this task group. Its ultimate goal is to standardize the enclosure of PV connectors (i.e., National Electrical Manufacturers Association to ensure there are no safety hazards that may occur when mating unlike connectors or mating connectors that have not been tested together. This is a long-term solution that will need industry leader support to help implement. Currently, there is an effort within NEMA to develop testing standards to address this issue.

Standards Activities

Task Leaders

Michael Kempe, David Miller — NREL, representing the Americas
Alan Xu — Canadian Solar, representing China

Other leaders are welcome.