What it is and where it lands
The Siemens 3RT1026-1AV00 is a SIRIUS power contactor in size S0, with three normally-open main contacts and screw-type terminals for both main and auxiliary circuits. It snaps onto 35 mm DIN rail per DIN EN 50022 or screws directly to a mounting plate — the dual fastening method gives the panel builder a clean option when rail space is tight. Rated for AC-3 duty at 400 V, it handles 11 kW motor loads — think conveyors, pumps, and compressors in a standard 400 V three-phase line. The AC-4 rating at 15.5 A covers reversing or inching applications where the contactor breaks full-load current.
What the ratings mean for fit
The AC-3 11 kW at 400 V is the rating that governs most motor-switching applications. That's a 3-pole contactor sized for a 22 A full-load current class motor on a 400 V line, with the electrical life typical of the S0 frame — 10 million operations mechanical, though the electrical life at full AC-3 load will be lower. For resistive or lightly inductive loads, the AC-12 rating of 10 A continuous gives a ceiling. Short-circuit coordination is specified with two fuse classes: Type 2 coordination requires 35 A gL/gG fuses (the contactor survives the fault essentially undamaged); Type 1 allows 100 A fuses but the contactor may need replacement after a fault. That's a real decision point for the panel designer targeting a specific SCCR. The contactor carries IP20 on the front (finger-safe when installed in an enclosure) and IP00 at the terminals — meaning the connection points are not touch-protected on their own. Pollution degree 3 rating suits it for industrial environments with conductive dust or occasional condensation, typical for a control panel in a factory hall. Operating temperature range of -25 to +60 °C covers most indoor panel environments. The 45 mm width (3 module spaces on a DIN rail) and 91 mm depth fit standard S0 footprint — side-by-side mounting is permitted without derating, which matters when packing multiple contactors into a motor control center row.
Lifecycle and sourcing reality
RoHS compliance date of July 1, 2006 confirms it meets the original EU RoHS directive. The IEC 81346-2 reference code Q (switching device) is standard for panel documentation.
Terminal wiring details
Main circuit screw terminals accept solid or stranded copper: 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), or max 2x 4 mm². The auxiliary/control circuit terminals take larger wire: 2x (1 to 2.5 mm²), 2x (2.5 to 6 mm²), or max 2x 10 mm². AWG equivalents are listed for both — 2x (16 to 12) and 2x (14 to 10) for mains, 1x 8 for a single conductor.