SIRIUS 3RF33 solid-state contactor, 1-pole
The Siemens 3RF3320-1AA22 is a 1-pole SIRIUS 3RF33 solid-state contactor rated AC-1 at 20 A at 40 °C, with a dual-range control voltage of 24-230 V / 110-230 V AC. It terminates via screw terminals and is a current-production item, so it's a standard BOM line — not a last-time-buy scavenger hunt. The AC-1 rating (resistive load) is the one that governs here — 20 A at 40 °C means it's sized for heater banks, lighting panels, or transformer primaries where inrush isn't an issue. If you're switching motor loads, you'll need to check the AC-3 derating curve; the AC-1 figure alone doesn't cover inductive kick.
Control voltage and wiring
The control circuit accepts 24-230 V AC or 110-230 V AC — a wide-range input that simplifies panel wiring when you're mixing control transformers or feeding from different line voltages across a site. The screw terminals are standard for panel builders; strip length and torque spec are on the nameplate.