Siemens SIRIUS 3RU1126-4BB0 thermal overload relay for three‑phase motor protection, adjustable 14–20A, in good working used condition. This size S0 unit mounts directly to compatible Siemens SIRIUS contactors and provides Class 10 overload protection.
Brand: Siemens
Series: SIRIUS 3RU11
Model: 3RU1126-4BB0 (instruction order no. on label: 3ZX1012-0RU11-1AA1)
Type: Thermal overload relay for motor protection
Current setting range: 14–20A adjustable (front dial scale 12–18/20A, data sheet 14–20A)
Trip class: Class 10
Main circuit: 3‑pole, for three‑phase motors up to approx. 7.5 kW at 400V (per typical 3RU1126 data)
Auxiliary contacts: 1 NO + 1 NC (95–96, 97–98) for signalling/control
Operating voltage: up to 690V AC main circuit
Terminals: Screw terminals for main (T1/T2/T3) and auxiliary circuits, labelled on front.
Reset: Manual/automatic selector, front STOP and RESET pushbuttons with status window
Mounting: Contactor‑mount, size S0, part of SIRIUS Classic system
Country of manufacture: Made in Germany (on label)
Good working used condition, taken from an operating panel.
Front housing shows visible dirt/discoloration and minor surface scuffs from normal service; lettering and scales remain readable.
Terminal screws and mounting clips intact; bimetal adjustment dial and reset/stop buttons operate smoothly.
No original packaging, documentation, or matching contactor included; overload relay only as pictured.
Compatible with Siemens SIRIUS S0 contactors (e.g. 3RT1 series) for integrated motor starter assemblies.
Buyer should confirm motor full‑load current and frame size requirements match the 14–20A Class 10 range before installation.
Installation and setting should be performed by qualified electrical personnel in accordance with Siemens documentation and local standards.
