Solid-state overload relay for contactor mounting
The Siemens SIRIUS 3RB3026-1NB0 is a solid-state overload relay sized for the S0 frame, rated at 1.25 A thermal current and 690 V. It mounts directly onto a contactor, saving panel space compared to a separate base-mount relay.
Trip signalling and auxiliary contact
The relay includes an integrated auxiliary switch that signals a tripped condition — the product note reads "for message 'tripped'". The signalling contact is rated at 2 A at 24 V, 0.55 A at 60 V, 0.3 A at 125 V, and 0.11 A at 220 V, with higher ratings on the main contact path: 4 A at 120 V and 3 A at 230 V. This lets the relay drive a PLC input or indicator lamp directly without an interposing relay.
It withstands 15g / 11 ms shock (IEC 60068-2-27) and vibration of 1-6 Hz at 15 mm amplitude and 6-500 Hz at 20 m/s² for 10 cycles. Mounting position is unrestricted. The screw terminals accept 1x (0.5 to 4 mm²) solid or 2x (0.5 to 2.5 mm²) stranded, with M4 screws for the main contacts. Dimensions are 45 mm wide, 87 mm high, 84 mm deep.