What it is and where it fits
The Siemens 3RT2024-1AP04-ZX95 is a SIRIUS power contactor in the S0 frame size — the middle workhorse of the SIRIUS line, sized between the compact S00 and the larger S2/S3 frames. It measures 45 mm wide, 85 mm tall, and 141 mm deep, and mounts via screw or snap-on onto 35 mm DIN rail per DIN EN 60715. That 141 mm depth is the dimension you need to check against enclosure back-panel clearance; the 45 mm width tells you how many slots it eats on the rail. The coil is 24 VDC with screw-type terminals — no auxiliary switch built in (spec lists "Auxiliary Switch: No"), so if you need N/O or N/C feedback for the PLC or a seal-in circuit, you'll add a separate auxiliary contact block that snaps onto the front. Rated operational current at 480 V hits 11 A, which puts it solidly in the range for smaller motor loads — think fractional-horsepower pumps, fans, or small conveyors out on the route. Operating temperature range is -25 to +60 °C during operation, with storage from -55 to +80 °C. That -25 °C low end matters if the panel sits in an unheated space — no worries about the coil refusing to pull in on a cold morning. The mounting position is forgiving: +/-180° rotation on a vertical surface, plus +/-22.5° tilt forward or backward, so it'll fit into tight retrofit panels where you're working around existing wireway.
Wiring and terminal details
Main contacts accept solid or stranded wire from 1 to 10 mm². The coil terminals use a different gauge range: 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²) solid or stranded. That's a common pattern on SIRIUS contactors — the coil circuit is lower-current, so the terminals are sized for smaller wire. When you're pulling the old contactor off the rail, note the arcing time on this one: 10 to 10 ms at AC, with a switching frequency up to 1,000 operations per hour for AC-3 duty. That's plenty for a typical motor start cycle.