What this direct starter is wired for
The 3RA2120-1FD24-0BB4: It ships with the 3RT2024-1BB40 contactor and the 3RA2921-1BA00 link module already integrated — no separate wiring between the two components.
Panel fit — busbar snap-on and clearances
This starter snaps directly onto 60 mm busbar systems, so it wires up clean without a separate DIN-rail bracket for the busbar feed. At 45 mm wide, 165 mm deep, and 260 mm tall, it fits a standard S0 feeder footprint — the depth is the dimension that matters most when laying out the gland plate and door clearance. Required free space around the unit: 50 mm above, 20 mm below, 20 mm to the side, and 20 mm forward — zero clearance needed behind the mounting surface. The main circuit uses screw-type terminals, which I prefer for torque-verified connections on motor feeders — no spring clips that can loosen under vibration.
Active production — sourced per BOM
The 24 V DC coil voltage matches common control-voltage rails in modern panels — no separate transformer tap needed for the starter coil.