The Siemens 3RA2225-4ED27-0AK6 is a SIRIUS 3RA2 non-fused reversing motor starter in size S0, meaning it combines two contactors and a thermal overload relay in one package to reverse a three-phase motor without needing separate reversing contactor assemblies. Rated 27 A at 480 V and 27 A at 600 V in AC-3 duty, it handles motor loads up to 20 hp at 460/480 V and 25 hp at 575/600 V — typical for reversing conveyors, hoists, or pump applications where direction change is needed. The thermal bimetallic overload relay is set to Trip Class 10, so it protects motors with short starting times (under 10 seconds) — common for fans and centrifugal pumps, but not for high-inertia loads that need Class 20 or 30. Coil voltage is dual-rated: 88-121 V at 50 Hz and 96-132 V at 60 Hz, covering common control transformer taps across North American and European line frequencies.
Snaps directly onto 60 mm busbar systems — no separate mounting plate needed for panel builds where busbar distribution is already in place. Mounting position is vertical only; dimensions are 260 mm height, 90 mm width, 155 mm depth, with clearance requirements of 30 mm upward, 10 mm forward, 10 mm downward, 9 mm at the side, and 0 mm backward. Main contact wiring accepts stranded conductors from 1 to 10 mm², or two conductors of 2.5 to 6 mm² each — useful for paralleling feeds in high-current reversing circuits. The supplied contactor is a 3RT2027-1AK60 and the link module is 3RA2921-1AA00; the circuit-breaker size is S0, matching the feeder size for coordinated Type 1 or Type 2 protection schemes.