SIRIUS S0 contactor — panel fit and coil choice
The Siemens 3RT2326-1AL20-4AA0 is a SIRIUS S0 contactor with an AC-operated coil terminated at screw-type terminals. The AC coil is rated at 230 V at both 50 Hz and 60 Hz, drawing 0.25 A at 50 Hz and 0.28 A at 60 Hz. That means the coil inrush and hold current are modest — a standard 230 V control transformer or a PLC digital output driving an interposing relay can handle it. The operating temperature range is -25 to +60 °C, with storage from -55 to +80 °C, so it handles warm panel interiors without derating up to 60 °C ambient. The auxiliary switch is included as standard (one N/O + one N/C, typical for the S0 frame), with contact ratings spanning 24 V to 600 V AC. At 24 V it switches 10 A; at 230 V it switches 10 A; at 400 V it switches 3 A; at 600 V it switches 0.1 A. These ratings cover pilot duty and control circuit isolation across common control voltages.
Wiring and clearance
Auxiliary contacts accept 2x (0.5 to 1.5 mm²) solid or 2x (0.75 to 2.5 mm²) stranded — typical for control wiring with ferrules. That is tight enough for dense DIN-rail layouts but leaves room for finger-safe wiring ducts. That helps when the contactor sits in a swing-frame panel or a slanted enclosure.