SIRIUS solid-state overload relay — 3RB3026-2RE0
The Siemens 3RB3026-2RE0 is a SIRIUS solid-state overload relay in Size S0, rated for a thermal current of 0.4 A and Trip Class 20E. The integrated auxiliary switch provides a "tripped" message signal — useful for feeding a PLC or indicator lamp when the relay has operated.
Class 20E means the relay allows a 20-second trip delay at 7.2× current setting — standard for general-purpose motor starting where the inrush is moderate (pumps, fans, compressors). The 0.4 A thermal current sets the motor FLA it protects; this is a low-current unit suited for small motors or control transformers. The auxiliary contact ratings cover both AC and DC signal circuits: 4 A at 120 V AC, 2 A at 24 V DC, and 0.55 A at 60 V DC — enough to drive a contactor coil or a PLC input directly.
Size S0 footprint: 45 mm wide, 109 mm high, 85 mm deep. Mounts in any position on the contactor — no DIN rail needed. Spring-loaded terminals accept 2× (0.25…1.5 mm²) solid/stranded or up to 1× 10 mm² stranded for the main circuit. Shock rated at 15g / 11 ms; vibration resistance per 1–6 Hz, 15 mm and 6–500 Hz, 20 m/s².