The 3RF3320-1DA22 is a SIRIUS 3RF33 solid-state contactor, 1-pole, rated 20 A in AC-1 duty at 40 °C. The control voltage accepts 24-230 V or 110-230 V AC, giving flexibility across common control circuits without needing a separate transformer. It is described as short-circuit-proof with a B miniature circuit breaker, meaning the internal semiconductor design coordinates with a standard B-curve MCB up to the rated current — no separate semiconductor fuse required for branch-circuit protection in typical resistive-load panels. The screw terminal connection suits panel wiring where ring or fork terminals are preferred over spring-cage; the 1-pole configuration switches one line in a single-phase circuit or one phase of a three-phase resistive bank.
RoHS compliance is documented since 15-01-24;
The 27 mm width (1.5 modules) is compact for a 20 A solid-state contactor, leaving room for adjacent motor starters or terminal blocks. In a cold-storage or refrigeration panel, the solid-state design means no contact wear from repeated cycling of resistive loads like defrost heaters or crankcase heaters — it runs cold and stays cold in terms of switching life.