The 3RT1017-1AB01-0UA0: This is a size S00 power contactor from the Siemens SIRIUS family, rated for motor switching at 5.5 kW at both 500 V and 690 V. The 24 VAC coil (50/60 Hz) pulls in reliably across 0.8 to 1.1 times rated voltage at 50 Hz and 0.85 to 1.1 at 60 Hz — so a 24 V control transformer with reasonable regulation will hold it in. The AC-4 rating of 8.5 A at 400 V tells you it handles reversing or inching duty on smaller motors; for straight across-the-line starting (AC-3), the 5.5 kW figure at 500 V and 690 V is the one to size against. The auxiliary contact block is rated for 10 A at 24 V (AC-12), dropping to 6 A at 230 V and 3 A at 400 V — enough for pilot duty on a PLC input or a small relay coil, but watch the voltage derating if you're switching a 400 V control circuit. Type 2 coordination requires a 20 A gL/gG fuse upstream; Type 1 allows a 35 A fuse. That's the selectivity boundary — if the panel spec calls for Type 2 (no damage to the contactor on a short circuit), stay with the 20 A fuse.
At 45 mm wide and 57.5 mm tall, it fits a standard 45 mm slot in a SIRIUS rail assembly — side-by-side mounting is permitted with 6 mm spacing to adjacent devices for heat dissipation. The IP20 finger-safe front and terminal covers mean it's suitable for enclosed panels only, not washdown environments. Screw terminals accept 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²) solid/stranded, with a maximum of 2x (0.75 to 4 mm²) — standard for a size S00 contactor.
Comparison to 3RT1017-1AP01
The 3RT1017-1AP01 is the same S00 frame with a 24 VDC coil instead of 24 VAC. If your control voltage is DC, the -1AP01 is the direct swap — same footprint, same terminal layout, same motor ratings. The -1AB01-0UA0 here is for AC control circuits only; feeding DC into an AC coil risks dropout or coil burnout.