SIRIUS 3RV1011-1HA10-0FJ0-ZX95 — motor protection circuit breaker, 8 A, Class 10
The Siemens SIRIUS 3RV1011-1HA10-0FJ0-ZX95 is a motor protection circuit breaker rated for 8 A continuous current with a Class 10 trip characteristic, designed to protect 3 kW motors at 400 V. It snaps onto a 35 mm DIN rail per DIN EN 50022 and occupies a 45 mm wide footprint — standard for this SIRIUS frame size. The 100 kA breaking capacity at 240 V and 50 kA at 400 V mean it can interrupt high-fault currents without cascading upstream, which matters when the panel SCCR must hit a specific number. Phase failure detection is built in; ground fault detection is not. The IP20 front protection keeps fingers out but expects enclosure-rated surroundings.
What the ratings mean for fit
The 8 A continuous rating sets the motor FLA it can carry without nuisance tripping — pair it with a motor drawing up to that nameplate. Class 10 trip means it opens within 10 seconds at 600% of the thermal setting, which protects a motor during stall or locked-rotor conditions without tripping on normal starting inrush. The 3 kW at 400 V is the typical 4-pole induction motor it maps to. Breaking capacity drops from 50 kA at 400 V to 3 kA at 500 V and 2 kA at 690 V — that derating curve matters if the supply transformer is sized for higher voltage. The 690 V rated insulation voltage and 6 kV surge voltage resistance confirm it handles industrial line transients. Operating temperature of -20 to +60 °C covers most panel environments; storage range of -50 to +80 °C is wider but governs handling, not running.
Panel integration and wiring
Mounts via screw and snap-on onto a 35 mm standard mounting rail per DIN EN 50022. Zero backward clearance and zero side clearance needed — it can sit flush against the backplane and adjacent devices, which saves rail space in a dense panel. Any mounting position works, so orientation is not a constraint. Main circuit terminals are screw-type, accepting solid or stranded conductors: 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²), with AWG equivalents of 2x (18 to 14) for main contacts. The auxiliary switch is present but carries 0 auxiliary contacts — that means the switch is a built-in trip indicator, not a separate contact block. Power loss at rated current in hot state is 9.25 W total, 3.1 W per pole — factor that into enclosure thermal calculations. Mechanical endurance is 100 000 cycles at a maximum switching rate of 15 cycles per hour at AC-3. Shock resistance of 25g for 11 ms covers most industrial vibration environments.