Motor duty and trip class
The 3RA2220-4EB27-0AP0: Class 10 trip curve means it holds in during a hard start and trips before the motor winding temperature climbs past the insulation class. The supplied contactor is a 3RT2027-1AP00, and the link module is 3RA2921-1AA00 — both factory-matched for the reversing interlock. No field wiring of mechanical interlocks; the reversing pair ships as a single assembly.
Panel fit and mounting
S0 feeder size, 265 mm tall, 90 mm wide, 120 mm deep. Snaps onto 35 mm DIN rail via the included adapter, or screw-mounts direct to a backplate. Vertical mounting position only — the arc chamber and contactor magnet need gravity to reset. Clearance requirements: 50 mm above, 32 mm in front, 10 mm below, 10 mm at the sides, zero behind. That front clearance is tight for a reversing starter with two contactors side-by-side — factor in the wire bending radius for the screw terminals.
Lifecycle and sourcing
The 3RA2220 series is Siemens' standard reversing starter line for S0 frames; no direct second-source cross-reference exists from other manufacturers.