Rapid shutdown device count

Counts devices for one array layout under rules as printed in the sources on the glossary page. A design aid, not the code text or your AHJ's ruling.

Modules in array

Strings (equal length)

Cold Voc per module (V)

NEC edition

Inverter position

Inverter distance from array (ft)

Modules per microinverter

Single-input device rating (V)

Dual-input device rating per input (V)

All parts are in one UL 3741 listing One- or two-family dwelling (600 V listing limit quoted by NACE; 1,000 V otherwise) Initiation switch is separate from the service disconnect

Assumed, not from a source: one string isolation device per string circuit, one initiation device, label counts, and the example cold Voc. Read the equipment instructions and listing.