Connector compatibility verification

Connector compatibility verification means confirming that mated DC connectors really fit and work together. This applies to new installations and to repaired circuits. It addresses connector defects caused by connector mismatch, where connectors from different manufacturers or of different types are joined. Mismatched connectors can cause contact corrosion, burnt connectors, arcing, open connections with no current flow and, in the worst case, fire. In humid weather they can also cause ground faults or partial inverter failure. If different connectors must be mated, get explicit confirmation of compatibility from the connector manufacturer, plus a third-party test report from a recognised lab such as TUV, VDE, UL, CSA or Intertek. Pay particular attention at string ends where extension cables are used, and at inverters or combiner boxes that were delivered with their own connectors. These are the places where mismatches most often occur. A limit to keep in mind is that no standard yet sets PV connector dimensions and tolerances. Connectors that look alike or are advertised as compatible may still seal poorly or use materials that do not work together. Mismatch problems develop slowly as contact resistance rises, and connectors are often fitted where routine visual inspection cannot reach them. That is why checking compatibility up front matters.

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• sentence 4: support check: partial - The SolarEdge text requires manufacturer verification and a third-party report from the listed labs, but it lists 'Bureau Veritas UL' rather than UL alone. It also frames them as one option when connectors aren't identical, which fits, but the 'recognised lab' generalisation is minor.
• sentence 5: support check: partial - The passage says most mismatches occur at string ends with extension cables or at inverters/combiner boxes delivered with incompatible connectors, but it doesn't say to pay particular attention there; that is an inferred recommendation. -->