MC4 connector

Common card · No. 394329

MC4 connectors are electrical connectors commonly used for connecting solar panels. The MC in MC4 stands for the manufacturer Multi-Contact (now Stäubli Electrical Connectors), and the 4 for the 4 mm diameter contact pin. MC4s allow strings of panels to be easily constructed by pushing the compatible connectors from adjacent panels together by hand, but require a tool to disconnect them to ensure they do not accidentally disconnect when the cables are pulled. The National Electrical Code (NEC) and the UL6703 standard for PV connectors specify that connectors have to be from the same type and brand to avoid the dangers of cross-mating. In addition, IEC 62548 ‘design requirements for PV Systems' require PV connectors to be of the same origin. Originally rated for 600 V, newer versions of the MC4 connector are rated at 1500 V, which allows longer series strings to be created.

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