The Siemens 3RB3046-2XX1 is a SIRIUS solid-state overload relay in Size S3, designed to protect motor circuits against overload and phase imbalance. The electronic overload release replaces the traditional bimetal strip, giving you a Class 20E trip curve — that means it allows a 20-second thermal memory at 600% of the set current before tripping, which is the standard match for standard induction motors starting across the line. It operates on 50-60 Hz supply and mounts in any position — stand-alone installation on a panel or DIN rail.
The 115 A thermal current is the continuous current the relay can carry without exceeding its temperature rise. That's the number you match to your motor FLA — not the trip class, not the short-circuit rating. The 1 000 V rated insulation voltage covers 400 V and 690 V systems with headroom. Auxiliary contacts are integrated, rated at various control voltages: 2 A at 24 V, 4 A at 120 V, 3 A at 230 V. The signaling contact (97/98) carries the "tripped" message — that's the dry contact that tells your PLC the relay has operated. Shock resistance is 8g / 11 ms for the signaling contact in tripped position, so it holds state under vibration on a conveyor line. Dimensions: 70 mm wide, 106 mm high, 124 mm deep. That's a standard S3 footprint — fits alongside a SIRIUS 3RT contactor of the same frame size. Wire range is 2x 0.25 to 1.5 mm² solid or stranded, terminated with a Pozidriv PZ2 screwdriver.
Substance prohibitance date is 03/01/2017, which aligns with the RoHS recast (EU 2015/863) compliance deadline. The part carries the standard SIRIUS documentation package — no special compliance paperwork needed beyond what Siemens publishes for the series.