Solid-State Overload Relay for Hazardous-Area Motor Protection
The Siemens SIRIUS 3RB2113-4SD0 is a three-pole solid-state overload relay with ATEX Ex II (2) GD certification (PTB 06 ATEX 3001). It mounts directly to a contactor, saving panel space at 45 mm width. Trip class is field-adjustable among CLASS 5E, 10E, 20E and 30E, letting the same part cover quick-trip motor starts (5E) through heavy-inertia loads (30E) without a hardware swap.
Switching Ratings and Auxiliary Circuit
Auxiliary contact ratings are given per voltage: 2 A at 24 V, 4 A at 120 V, 3 A at 230 V, and lower ratings at 60 V (0.55 A), 110 V (0.3 A), 125 V (0.3 A), and 220 V (0.11 A). These are the maximum switching currents for the internal solid-state output; the relay has no electromechanical auxiliary contacts (number of CO contacts for auxiliary contacts: 0). The control circuit uses spring-loaded terminals (2x 0.25–1.5 mm² solid or 2x 24–16 AWG), while the main circuit uses screw-type terminals (2x 0.25–1.5 mm² solid / 2x 18–14 AWG).
Environmental and EMC Robustness
Surge voltage resistance is rated at 6 kV, and the relay withstands burst transients per IEC 61000-4-4 at 2 kV on power ports and 1 kV on signal ports (severity level 3). Shock resistance is 15g / 11 ms. Storage and transport temperature range is -40 to +80 °C.