Siemens

Siemens 3RU1126-4BB0 Thermal Overload Relay

In stock, ready to ship

  • Manufacturer: Siemens

  • Product No.: 3RU1126-4BB0

  • Product Type: Thermal Overload Relay

  • Product Origin: Germany

  • Payment: T/T

  • Weight: 4780g

  • Shipping port: Xiamen

  • Warranty: 12 months

The Siemens 3RU1126-4BB0 is a thermal overload relay from the Siemens SIRIUS range. It is designed to protect electric motors from overheating caused by overload conditions or phase failure.

Technical Specifications

Feature Details
Product Brand Siemens SIRIUS
Relay Size S0 (compatible with S0 contactors)
Current Setting Range 14 A – 20 A
Mounting Type Direct mounting onto a contactor
Trip Class Class 10 (trips within 10 seconds at 6× rated current)
Auxiliary Contacts 1 NO (Normally Open) + 1 NC (Normally Closed)

Key Features & Functionality

Phase Failure Protection
The relay trips when one phase of the three-phase supply is lost, preventing potential motor damage.

Manual / Automatic Reset
Users can choose between:

  • Manual reset – requires a physical reset after tripping

  • Automatic reset – the relay resets automatically once it cools down

Ambient Temperature Compensation
Designed to operate reliably in ambient temperatures from −20 °C to +60 °C, minimizing the risk of false trips.

Stop / Test Button
Allows manual testing of the auxiliary contacts and provides a convenient way to stop the motor during maintenance checks.

Link copied