3RU2126-4DB0 Siemens Overload Relay, Get Quote

3RU2126-4DB0 – Siemens SIRIUS Thermal Overload Relay, 20-25A, In Stock

Buy the Siemens 3RU2126-4DB0, a SIRIUS 3RU2 thermal overload relay, 20-25A adjustable, CLASS 10, Size S0, for direct mounting on 3RT2 size 0 contactors (9-38A), screw terminal, manual/automatic reset. In stock and available for fast shipping. Get a quote today.

Key Technical Specifications

  • Product Type: Thermal overload relay, SIRIUS 3RU2 series
  • Overload Relay Size: S0
  • Compatible Contactor Size: S0 (3RT2 size 0, 9–38 A)
  • Current Adjustment Range: 20–25 A
  • Trip Class: CLASS 10
  • Auxiliary Contacts: 1 NO + 1 NC
  • Terminal Type: Screw (main and auxiliary circuit)
  • Reset Type: Manual or automatic (selectable)
  • Power Loss (AC hot operating state): 8.1 W total; 2.7 W per pole
  • Rated Insulation Voltage: 690 V
  • Rated Impulse Withstand Voltage (Uimp): 6 kV
  • Max. Permissible Voltage for Protective Separation: 440 V (ungrounded star point)
  • Phase Loss Sensitivity: Yes
  • Approvals: UL rated, worldwide (IEC and UL/CSA), ATEX/IECEx capable

Design and Performance

Current-Dependent Protection Against Overload and Phase Failure

Designed for inverse-time delayed protection of loads with normal starting against excessive temperature rises due to overload or phase failure, this relay is particularly flexible and cost-effective for a wide range of motor applications.

Direct, Space-Saving Contactor Mounting

Electrically and mechanically optimized to match 3RT contactors, the 3RU2126-4DB0 can be directly mounted onto compatible S0-size contactors to save panel space, in addition to standalone individual mounting.

Part of a Graduated Setting Range Family

For applications requiring a higher amp range, Siemens offers the 3RU2126-4NB0 (adjustable up to 28A), letting engineers select the exact overload relay setting range matched to their specific motor’s full-load current.

Worldwide Approvals for Global Deployment

Worldwide approvals (IEC and UL/CSA) and suitability for hazardous area applications (ATEX or IEC Ex) make this overload relay a straightforward choice for equipment destined for global and regulated markets.

Clear Trip Status Indication with Flexible Reset

The “Tripping” state is signaled by a switching position indicator, with resetting available manually or automatically after a recovery time has elapsed, giving flexibility to match reset behavior to the application’s safety requirements.

Why Buy the 3RU2126-4DB0 From Us

  • In stock and ready for immediate dispatch
  • Fast shipping on every order
  • Commercial advisory support to help you confirm compatibility with your 3RT2 contactor
  • Competitive pricing — get a quote in minutes

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