SIRIUS S0 direct starter — 25 A AC-3, snaps onto 60 mm busbars
The 3RA2120-4DD27-0FB4: It ships as a pre-assembled unit: the supplied contactor is 3RT2027-1FB40 and the link module is 3RA2921-1BA00, so it lands on the shelf ready to snap onto a 60 mm busbar system without piecing together separate components.
Panel fit and clearance — size S0 on 60 mm busbars
The starter measures 45 mm wide by 260 mm high by 165 mm deep, and is designed to snap vertically onto a 60 mm busbar system — no DIN rail adapter needed, it clips directly onto the busbar profile. Clearance requirements: 50 mm upwards, 20 mm forwards, 20 mm at the side, 10 mm downwards, and 0 mm backwards — the back of the unit sits flush against the panel backplane, so plan the busbar depth accordingly. Main circuit connections are screw-type terminals, sized for the S0 frame — expect to land up to 25 A motor feeders with standard ring or fork lugs.
Ambient limits and storage range
Operating ambient temperature range is -20 to +60 °C, with the same range for temperature compensation — the overload curve stays accurate across that band without manual adjustment. Storage and transport limits are wider: -50 to +80 °C, so the unit can sit in an unheated warehouse or truck without damage.