What this breaker is and where it fits
The Siemens 3RV1021-1EA10-ZW95 is a SIRIUS motor-protective circuit breaker rated for 4 A continuous current with a Class 10 trip characteristic, sized for a 1.5 kW motor at 400 V AC. It snaps onto a 35 mm DIN rail per DIN EN 50022 and uses screw-type terminals for the main and auxiliary circuits. The IP20 front face keeps live parts behind the panel door.
Breaking capacity and coordination
This breaker clears 100 kA at 400 V and 500 V AC, dropping to 6 kA at 690 V. That 100 kA figure means it handles high-fault conditions common on large-distribution panels without needing an upstream current-limiting fuse — saves a fuse holder and a panel cutout. At 690 V the lower 6 kA still covers most motor branch circuits; just verify your available fault current at that voltage.
Mounting and wiring
Width is 45 mm, height 97 mm, depth 96 mm. Zero clearance needed at the sides or rear — packs tight against adjacent devices. Screw terminals accept 2x (1 to 2.5 mm²) solid or stranded, or 2x (2.5 to 6 mm²) for heavier feeds. AWG 14 to 10 for the main contacts. Any mounting position works.