S0 direct-on-line starter, 20 A AC-3 — what it carries
The 3RA2120-4BA27-0BB4: That AC-3 rating means it switches squirrel-cage motors under starting and stopping conditions — the current during acceleration is the design load, not the locked-rotor inrush. The supplied contactor is a 3RT2027-1BB40 and the link module is 3RA2921-1BA00; the assembly ships as a coordinated pair, so you avoid the guesswork of matching contactor-to-overload ratings yourself.
DIN rail footprint and panel fit
Clearance around the unit: 50 mm above, 20 mm forward, 10 mm below, and 20 mm at the side. The 0 mm backward clearance means it can sit flush against the back panel — useful when the enclosure depth is tight.
Active production — sourcing posture
No stock-holding claim — each RFQ is handled individually.