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Catalogue · 6 products

Optimizer and rapid shutdown

Module-level electronics for a string inverter system: rapid shutdown devices that drop each panel's output to a safe voltage when the system is switched off, as the NEC requires on a rooftop array, and optimizers that let a shaded or mismatched panel stop dragging the rest of its string down.

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Tigo TS4-A-F and the RSS transmitter are the rapid-shutdown pairing for Tigo-compatible inverters; the TS4-A-O adds optimisation on the same platform. APsmart RSD-S and RSD-D and the Fonrich module are PLC rapid-shutdown units for inverters that support that standard. Check your inverter's compatibility list before choosing.

Rapid shutdown is a code requirement for roof arrays in the US, so plan one device per panel or per pair. Send us the inverter model and panel count and we will specify the set.

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