What this SIRIUS S3 power contactor is and what it handles
The Siemens 3RT1346-1AP00-4AA0 is a SIRIUS power contactor in size S3, built for switching motor loads and resistive circuits in industrial control panels. It mounts via screw and snap-on onto 35 mm or 75 mm standard mounting rail, so it drops into a DIN-rail enclosure without extra bracketry. The key motor ratings: 55 kW at 690 V AC-3 (the standard squirrel-cage motor duty), 55 kW at 500 V AC-3, and 45 kW at 400 V AC-2 (slip-ring motor or high-inertia starts). For the AC-4 reversing or plugging duty at 400 V it carries 80 A. That means this contactor handles a 75 HP motor at 480 V or a 55 kW motor at 690 V without needing to oversize. The insulation voltage is rated 1 000 V, and it operates from -25 to +60 °C ambient, storage from -55 to +80 °C. Pollution degree 3 means it's fit for industrial environments with conductive dust or condensation — no extra conformal coating needed for most panel builds.
Terminal capacity and wiring reality
Main circuit terminals are screw-type, accepting solid conductors 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), and max 2x (0.75 to 4 mm²). For the power side, stranded cable goes up to 2x (10 to 50 mm²). At 40 °C ambient the minimum permissible cross-section is 50 mm²; at 60 °C it derates to 35 mm². That's the thermal limit on the lug — not a suggestion. Auxiliary and control circuit wiring uses solid or stranded 2x (2.5 to 16 mm²). Side-by-side mounting is permitted, so you can gang multiple contactors on the rail without spacing gaps — useful for a motor control center bucket.
Coil and switching characteristics
The contactor's coil operates at 50 Hz with a voltage tolerance of 0.8 to 1.1 times rated. Switching times: arcing duration 10 to 15 ms, total make/break at AC 10 to 25 ms. Mechanical life is 10 000 000 operations typical. At AC-1 maximum switching frequency is 1 000 cycles per hour — fine for frequent cycling on resistive loads like oven banks. Auxiliary contact ratings: 10 A at 24 V, 6 A at 230 V, 3 A at 400 V, 2 A at 60 V, 1 A at 110 V, 0.3 A at 220 V. These cover PLC-level signals and small relay coils; watch the 220 V figure if you're switching an interposing relay at that voltage — it's only 0.3 A.
Enclosure protection and compliance
IP20 on the front with cover or box terminal; the terminal area itself is IP00 — so the panel enclosure provides the touch protection. The substance prohibitance date of 05/01/2012 aligns with RoHS compliance scope.