The Siemens 3RB2026-1SB0 is a SIRIUS solid-state overload relay — a CLASS 10E trip device that protects three-phase motor circuits from sustained overcurrent. It carries ATEX approval PTB 06 ATEX 3001 Ex II (2) GD, meaning it can be used in Zone 2 gas and Zone 22 dust hazardous areas when paired with an appropriate motor starter — a key spec for chemical, grain, or pharmaceutical lines where an arc from a failing thermal overload could ignite the atmosphere. The relay mounts directly onto a contactor (contactor mounting), saving DIN-rail space in a crowded panel.
Integration notes
Wiring: main circuit terminals accept solid 0.5 to 4 mm² or 2× (0.5 to 2.5 mm²) — fine-stranded with ferrules also supported down to 0.5 mm². Auxiliary/control terminals use the same screw-type clamp, accepting 2× (0.5 to 2.5 mm²) solid or 2× (0.5 to 1.5 mm²) fine-stranded. The 6 kV surge voltage rating (IEC 61000-4-5) and 2 kV burst immunity (IEC 61000-4-4, severity 3) mean it holds up in industrial environments with motor drives and contactor switching nearby. Shock rated to 15g / 11 ms — fine for machine-mounted enclosures on punch presses or conveyors. The 0.02 W dissipation per pole keeps heat low inside a sealed cabinet.