What this 0.8 A SIRIUS breaker does in a motor branch
The Siemens 3RV1021-0HA10-0FJ0-ZX95 is a SIRIUS motor protection circuit breaker rated 0.8 A continuous current, designed to protect a 0.18 kW motor at 400 V. It snaps onto 35 mm DIN rail per EN 50022 and uses screw-type terminals for the main circuit — no special tooling needed for a panel swap. The CLASS 10 trip curve means it clears a stalled-rotor fault fast enough to keep the motor winding insulation intact, which is the standard for standard induction motors driving pumps, fans, and conveyors.
Breaking capacity and fault clearing
This breaker carries a 100 kA breaking capacity all the way from 240 V through 690 V AC. That is the full rated interrupting rating across the voltage range — no derating curve to watch at higher voltages. For a panel with a transformer-fed 400 V supply and a high available fault current, this unit clears a bolted fault without upstream fuses needing to open. Phase failure detection is built in; ground fault detection is not, so if that is required, a separate residual-current device goes upstream.
Mounting and clearances
Mounts in any position — vertical, horizontal, upside down — on 35 mm DIN rail. Zero clearance needed at the back or sides, so it packs tight against adjacent devices in a crowded enclosure. Front face carries an IP20 finger-safe shroud. The 45 mm width matches the standard SIRIUS 3RV1 footprint; a 96 mm depth means it clears a 100 mm deep enclosure door without interference.