S0 reversing starter with Class 10 overload protection
The Siemens SIRIUS 3RA2220-4BB26-0AP6 is a non-fused reversing motor starter in the size S0 footprint, designed for controlling motors that need to run in both directions — conveyors, hoists, or any reversing drive train.
Snap-on DIN rail, vertical only, 265 mm tall
Mounts via snap-on fastening onto 35 mm standard DIN rail, with the mounting position restricted to vertical — no horizontal or inverted mounting allowed, so plan the rail layout accordingly. The envelope measures 265 mm high, 90 mm wide, and 120 mm deep — the depth is the critical dimension for enclosure depth clearance, especially when the reversing starter is paired with the supplied contactor 3RT2026-1AP60 and link module 3RA2921-1AA00. Clearance requirements: 30 mm upwards, 10 mm forwards, 10 mm downwards, 9 mm at the side, and 0 mm backwards — the backwards zero means the back of the unit can sit flush against the panel backplate.
Wire sizing and ambient limits
Main contact terminals accept stranded wire from 1 to 10 mm², or two conductors of 2.5 to 6 mm² each — useful for daisy-chaining power through the starter without an extra terminal block. The degree of pollution is rated 3, meaning the unit is designed for conductive pollution environments typical of industrial control panels — no additional conformal coating required for normal factory air.
No stock-holding claim — quoted per BOM quantity. The substance prohibitance date of 03/01/2017 indicates RoHS compliance per Siemens' declaration, covering the EU RoHS directive.