59 A AC-3 at 400 V — the number that sizes the motor branch
The 3RA2150-4XA37-0AP0: This is not a thermal continuous rating — it's the making and breaking capability under full-load starting conditions. It's the standard choice for pumps, fans, and compressors that accelerate within a few seconds. The maximum system voltage is 690 V AC-3, so this starter handles 400 V and 480 V networks with headroom, but not 690 V systems — that's the ceiling, not a recommendation for continuous 690 V motor operation.
S2 frame — panel fit and mounting reality
Clearance around the unit: 50 mm above, 32 mm in front, 10 mm below, and 10 mm to each side. The zero backwards clearance means it sits flush against the back panel — no extra depth needed behind the DIN rail.
What's in the box — pre-assembled, no separate ordering
This is a factory-assembled direct online starter that ships with the contactor (3RT2037-1AP00,) and the link module (3RA2931-1AA00,) already integrated. No separate contactor or bus-bar ordering — it's one order code for the complete motor branch. The overload release is thermal bimetallic — field-adjustable, no electronic drift, and no auxiliary power needed for the trip function. The switching contact is electromechanical, not hybrid or solid-state, so it's a direct replacement for existing SIRIUS installations. Control coil voltage is 230 V at 50 Hz — single nominal, not a dual-voltage coil. Confirm your control transformer matches before wiring.
Lifecycle and compliance — active, no obsolescence concern
Operating ambient range is -20 to +60 °C with storage/transport range of -50 to +80 °C.