What this 3RV5041-4LA10 does on your motor circuit
This is a Siemens SIRIUS Size S3 motor protection circuit breaker rated 90 A at AC-3 duty on 400 V. That 90 A figure is what it carries under motor starting conditions — the magnetic short-circuit trip and the thermal Class 10 overload release work together to protect a motor branch. The frame is Size S3, which tells you the physical envelope and terminal capacity — it accepts up to 70 mm² solid or stranded on the line and load sides, with box-type screw terminals torqued to 4–6 N·m.
Sourcing and lifecycle — still a current catalog item
It carries the usual compliance documentation for a European-market industrial breaker — RoHS substance prohibition dated July 2006, which covers the original EU RoHS directive. The surge voltage resistance is rated 6 kV, and it's built to handle 25 g / 11 ms shock per IEC 60068-2-27, so it's suited for applications with moderate vibration like conveyor drives or pump skids.
If you're looking at the 3RV6021-4DA10 as a possible cross, the main difference is frame size and current range. The 3RV5041-4LA10 is a Size S3 breaker rated 90 A; the 3RV6021-4DA10 is a larger-frame device (Size S6 or similar depending on variant) that covers a higher current band. The 3RV5041-4LA10 will not drop into a panel wired for the 3RV6021-4DA10 without reworking the bus bars and the mounting footprint — the S3 frame is physically smaller. Stick with the 3RV5041-4LA10 if your motor FLA is under 90 A and your existing panel has S3 cutouts.
Mounting and wiring in the panel
The screw terminals accept two conductors per pole up to 16 mm² solid or 50 mm² finely stranded with ferrules. Torque to 4–6 N·m. The breaker is rated for any mounting orientation, so you can lay it on its side if the enclosure depth is tight, but the 167 mm forward clearance (cover swing) still needs to be free.