53 kA at 400 V — what that means for the panel
The 3RA6120-2AP32: In a panel with a transformer-fed bus that delivers 50 kA prospective short-circuit current, this starter clears the fault without needing a current-limiting fuse ahead of it. The unit is a direct starter (non-reversing), rated for continuous operation per IEC 60947-6-2. It handles a 90 W motor load at 400 V, drawing 0.4 A at 400 V AC.
Trip class and thermal protection — adjustable CLASS 10/20
The overload relay is adjustable between CLASS 10 and CLASS 20. CLASS 10 trips in under 10 seconds at 7.2× FLC — use it for submersible pumps or compressors that need fast lock-rotor protection. CLASS 20 allows a longer start for high-inertia loads like fans or centrifuges. The setting is a simple dial on the front; no swap-out of a separate overload block. Power dissipation is 6 W AC maximum, 5.1 W DC maximum — low enough that several starters can sit side-by-side on the DIN rail without forced cooling, provided ambient stays within -20 to +60 °C during operation.
Mounting and wiring — DIN rail, spring terminals
Any mounting position is allowed, though vertical orientation on the rail is recommended for optimal heat dissipation. No screw torque to check — strip, insert, release. The control circuit uses the same spring-clamp interface.
Environmental robustness — vibration and shock
Vibration resistance tested to 10 cycles at 4–5.8 Hz with 15 mm amplitude, then 5.8–500 Hz at 20 m/s². Shock resistance is 60 m/s² (6 g) with 10 ms half-sine, three shocks per axis. This means the starter holds its settings and contact alignment on a conveyor drive or a compressor skid without nuisance trips. Storage and transport temperature range is -55 to +80 °C — the unit can sit in an unheated warehouse or truck without damage. Pollution degree 3 means it tolerates conductive dust and condensation typical of industrial enclosures.