The Siemens 3RT1034-1AL24 is a SIRIUS S2-frame power contactor rated for motor switching up to 18.5 kW at 500 V AC-3 duty and 10 kW at 690 V AC-3, making it a fit for 400 V to 690 V three-phase motor loads in industrial control panels. Its AC-2 rating of 15 kW at 400 V covers slip-ring motor or high-inertia starts where the inrush extends beyond the AC-3 window.
The headline AC-3 rating of 18.5 kW at 500 V tells you the contactor can handle a standard three-phase squirrel-cage induction motor of that power through normal starting and running — that's the common duty for pumps, fans, and conveyors. The 10 kW at 690 V rating extends its reach into higher-voltage installations common in mining or marine applications. The AC-4 rating at 400 V (not fully listed in the excerpt) would govern plugging or inching duty; the 250 cycles/hour maximum at AC-4 sets the thermal limit for reversing or jogging applications. Side-by-side mounting is permitted, which saves rail space in multi-contactor assemblies like star-delta starters. Operating temperature spans -25 °C to +60 °C, with storage from -55 °C to +80 °C.
At 55 mm wide and 112 mm tall, the S2 frame fits standard 35 mm DIN rail with snap-on mounting. Depth of 164 mm accounts for the screw terminals and arc chamber — verify clearance to the gland plate or enclosure door. The screw terminals accept solid conductors up to 2x 4 mm² and stranded up to 2x 25 mm², covering most motor circuit wiring up to the rated current. Coil operating range is 0.8 to 1.1 times rated voltage at 50 Hz and 0.85 to 1.1 at 60 Hz. Arcing time of 10 to 15 ms and AC operating time of 7 to 20 ms are typical for this contactor class.