The Siemens SIRIUS 3RT1025-1BE84 is a size S0 power contactor rated for motor switching in AC-3 duty at 10 kW on a 500 V line and 11 kW at 690 V. The AC-4 reversing/inching rating is 15.5 A at 400 V. This covers the common motor sizes for small pumps, fans, and conveyors in a 45 mm wide package. The coil draws 5.4 W DC both on pick-up and hold, so the control transformer and DC supply don't need to handle a surge — it's a constant-load coil. That simplifies sizing for a 24 VDC control bus.
Front face is IP20 — finger-safe for the panel interior. The terminal area is IP00, meaning the connection points are exposed and require the panel enclosure to provide the overall ingress protection.
Type 1 coordination (contactor may need replacement after a fault) allows a 63 A gL/gG fuse. This gives the panel builder a clear choice: smaller fuse for higher uptime, larger fuse for simpler coordination with downstream motor protection.