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Siemens 3RK4340-3DR51-1BA0 — Motor Starters

Siemens 3RK4340-3DR51-1BA0 SIRIUS Reversing Starter

MPN3RK4340-3DR51-1BA0

Siemens SIRIUS 3RK4340-3DR51-1BA0, I/O controlled reversing motor starter, 1.25 A AC-3 at 400 V, CLASS 10 bimetal protection, IP55 enclosure.

Siemens 3RK4340-3DR51-1BA0 datasheet (PDF)
Sourced new & surplus through independent channelsAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

3RK4340-3DR51-1BA0 — Identification
ParameterValue
Product designationmotor starter MCU, I/O controlled
Main circuit poles3
BrandSIRIUS
Product design / constructionreversing starter
Reference designation (IEC 81346-2)Q
3RK4340-3DR51-1BA0 — Protection & Tripping
ParameterValue
Trip classCLASS 10
Overload release setting range (current)0.9 ... 1.25 A
Duty / utilization type (IEC 60947-6-2)1
3RK4340-3DR51-1BA0 — Contacts & Control
ParameterValue
Switching contact typeelectromechanical
3RK4340-3DR51-1BA0 — Communication
ParameterValue
AS-Interface protocol supportNo
3RK4340-3DR51-1BA0 — Mechanical & Connection
ParameterValue
Main circuit connection typescrew-type terminals
Mounting position+/-180° rotation possible on vertical mounting surface; can be tilted forward and backward by +/- 22.5° on vertical mounting surface
Width182 mm
Height220 mm
Depth145 mm

Product details

SIRIUS reversing starter, I/O controlled

It is designed for direct-on-line reversing of three-phase motors up to 1.25 A at AC-3 duty on a 400 V supply. The CLASS 10 bimetal overload relay provides motor protection within the same enclosure, rated for a 340 to 440 V operating voltage range. The control supply is 24 V DC nominal, accepting 20.4 to 26.4 V DC.

The 182 mm width, 220 mm height, and 145 mm depth fit standard SIRIUS enclosure footprints. No bus communication (PROFINET, PROFIBUS, or AS-Interface) is integrated — control is via hardwired I/O. Short-circuit protection is provided by upstream circuit-breakers. The electromechanical switching contacts and bimetal overload element require no auxiliary power for the motor protection function, only the 24 V DC control supply.

Frequently asked questions

Where can I buy 3RK4340-3DR51-1BA0 and get a price?

This part is sourced to order against an RFQ through independent distribution. Submit a request for quote to confirm current pricing and availability.

Is 3RK4340-3DR51-1BA0 a reversing starter?

Yes, the product design is a reversing starter, meaning it integrates two contactors in a mechanically interlocked arrangement for forward/reverse motor control.

What does IP55 mean on a 3RK4340 series starter?

IP55 means the enclosure is dust-protected and protected against water jets from any direction. It is suitable for outdoor cabinets, washdown areas, or environments with hose-down cleaning.

MPN
3RK4340-3DR51-1BA0