Siemens SIRIUS 3RU1126‑4DB0 thermal overload relay, adjustable 20–25A Class 10, new and never used in the original Siemens packaging. This overload relay provides current‑dependent motor protection with phase‑loss sensitivity and is designed for direct mounting on S0 size Siemens contactors.
Brand: Siemens
Family: SIRIUS 3RU11 thermal overload relays
Model: 3RU1126‑4DB0
Type: Thermal overload relay for motor protection
Frame size: S0
Current adjustment range: 20–25A (front blue dial)
Tripping class: Class 10 (normal‑start applications)
Poles: 3‑pole main circuit (T1, T2, T3)
Auxiliary contacts: 1 NC + 1 NO (95‑96 / 97‑98)
Reset modes: selectable manual (M) or automatic (A) reset
Test function: TEST button for trip check
Mounting: direct mounting on 3RT1023, 3RT1024, 3RT1025, 3RT1026 contactors or separate DIN‑rail/base mounting.
Terminals: screw terminals for main and auxiliary circuits
Standards: IEC 60947‑4‑1 / VDE 0660 motor protection standards.
New old stock; relay has not been wired or operated.
Original Siemens cardboard box present; shows noticeable shelf wear, edge creasing and dirt but is intact.
Front housing, terminals and adjustment dial appear clean with sharp markings; device remains seated in factory packaging.
Intended for protecting motors with full‑load current between 20 and 25A; buyer should match setting to motor nameplate current and ensure proper coordination with upstream protection.
Part of the modular SIRIUS system; pairs with compatible S0 contactors to form a compact motor starter with integrated overload protection and auxiliary signalling.
