Certificates, Test Reports and Model Scope: What Buyers Should Verify

Surge protective devices and residual current circuit breakers often share the same board, but they solve different problems. The SPD clamps transient overvoltage from lightning or switching. The RCCB opens when leakage current suggests a shock or insulation fault. If they are coordinated poorly, the RCCB trips on SPD operation, or the SPD never sees a short enough earth path.

Place the SPD where the energy actually arrives

For a 1000 V PV array, a Type 1+2 DC SPD such as Pronto KNY2-40PV belongs at the combiner or inverter DC input, with short, equal-length leads to the earth bar. On the AC side, a matching AC SPD sits after the incoming isolator.

Keep the RCCB selective

A 100 mA or time-delayed RCCB on a PV feeder is less likely to nuisance-trip when SPDs fire than a 30 mA instantaneous device on the same circuit. Final circuits that need personal protection still use 30 mA devices downstream.

One board, one test plan

After installation, test the RCCB from its front button, inspect SPD status windows, and record both in the handover pack. Distributors and EPCs can then show inspectors a complete protection chain rather than a mix of unmatched parts.