The Siemens SIRIUS 3RV2121-4EA10 Motor Protection Circuit Breaker (MPCB) is a high-performance industrial protection device engineered for motor overload protection, short-circuit protection, phase failure protection, and safe motor isolation. Part of the globally trusted Siemens SIRIUS 3RV2 series, this Size S0 Motor Protection Circuit Breaker integrates a Class 10 thermal overload relay and magnetic short-circuit protection into one compact unit, making it the ideal solution for motor control centers (MCC), industrial automation systems, OEM machinery, electrical control panels, process industries, manufacturing plants, and power distribution applications. It is specifically designed to protect three-phase induction motors from overload, locked rotor, and fault conditions while ensuring maximum system reliability and operational safety.
The 3RV2121-4EA10 features an adjustable thermal overload current range of 27–32A, 400A magnetic short-circuit release, Class 10 tripping characteristics, 3-pole configuration, screw terminal connections, and standard switching capacity. With a rated insulation voltage of 690V AC, high breaking capacity, and excellent mechanical endurance, it delivers dependable protection in demanding industrial environments. It integrates seamlessly with Siemens SIRIUS contactors to build compact and efficient Direct-On-Line (DOL) and star-delta motor starter combinations, reducing panel space and simplifying installation.
The Siemens 3RV2121-4EA10 Motor Protection Circuit Breaker is widely used in pump control panels, compressors, conveyor systems, HVAC equipment, water treatment plants, packaging machinery, textile machines, food processing units, mining equipment, cement plants, steel industries, and factory automation systems. Its robust construction, high electrical durability, and Siemens-quality engineering make it a preferred choice for industrial motor protection applications requiring long-term reliability and low maintenance.
At SB Smart, we supply 100% genuine Siemens SIRIUS Motor Protection Circuit Breakers (MPCB), contactors, overload relays, soft starters, MCCBs, MCBs, and industrial automation products at competitive prices with expert technical support, GST billing, bulk order assistance, and fast PAN India delivery.
Genuine Siemens SIRIUS 3RV2 Motor Protection Circuit Breaker
Model: 3RV2121-4EA10
Frame Size: S0
Adjustable Thermal Overload Range: 27–32A
Magnetic Short-Circuit Release: 400A
Class 10 Thermal Overload Protection
Standard Switching Capacity
3-Pole Configuration
Screw Terminal Connections
Rated Insulation Voltage: 690V AC
Integrated Overload, Short-Circuit & Phase Failure Protection
Compatible with Siemens SIRIUS Contactors
Compact Space-Saving Design
High Mechanical & Electrical Endurance
Suitable for DOL and Star-Delta Motor Starters
Motor Control Centers (MCC)
Industrial Automation Panels
Motor Starter Assemblies
DOL Motor Starters
Star-Delta Starter Panels
Pump Control Panels
Compressors
Conveyor Systems
HVAC Systems
Water Treatment Plants
Packaging Machinery
Textile Industries
Food Processing Plants
Manufacturing Facilities
OEM Electrical Panels
Protects motors against overload and short-circuit faults
Integrated thermal overload relay eliminates separate overload devices
Phase failure protection improves motor safety
Reduces downtime and maintenance costs
Compact design saves valuable panel space
Easy installation with screw terminals
Reliable operation in harsh industrial environments
Long mechanical and electrical service life
Ideal for continuous-duty industrial motors
100% Genuine Siemens Products
Best Siemens MPCB Price in India
Expert Technical Support
Bulk Order Assistance
Fast PAN India Delivery
Secure Packaging
GST Invoice Available
Trusted Industrial Electrical Supplier
Reliable After-Sales Support
The Siemens 3RV2121-4EA10 is a Motor Protection Circuit Breaker (MPCB) designed to protect three-phase motors against overload, short-circuit, and phase failure while providing safe electrical isolation.
The breaker provides an adjustable thermal overload setting from 27A to 32A.
It features a 400A magnetic short-circuit release for rapid fault interruption and reliable motor protection.
Yes. The 3RV2121-4EA10 is compatible with Siemens SIRIUS contactors and is ideal for DOL starter panels, star-delta starters, and motor starter combinations.
The breaker is equipped with screw terminal connections, ensuring secure and vibration-resistant wiring in industrial control panels.
Yes. SB Smart supplies 100% genuine Siemens SIRIUS Motor Protection Circuit Breakers with competitive pricing, expert technical support, GST invoices, and fast delivery across India.
| Parameter | Specification |
|---|---|
| Brand | Siemens |
| Series | SIRIUS 3RV2 |
| Model Number | 3RV2121-4EA10 |
| Product Type | Motor Protection Circuit Breaker |
| Function | Motor Protection with Overload Relay Function |
| Frame Size | S0 |
| Tripping Class | Class 10 |
| Thermal Overload Release (A-Release) | 27.00–32.00 A |
| Short-Circuit Release (N-Release) | 400 A |
| Number of Poles | 3 |
| Rated Operational Voltage | 20–690 V AC |
| Rated Operational Current | 32 A |
| Rated Insulation Voltage | 690 V |
| Rated Impulse Withstand Voltage | 6 kV |
| Frequency | 50/60 Hz |
| Connection Type | Screw Terminal |
| Switching Capacity | Standard |
| Degree of Protection | IP20 |
| Mechanical Endurance | 100,000 Operating Cycles |
| Electrical Endurance | 100,000 Operating Cycles |
| Operating Temperature | -20°C to +60°C |
| Storage Temperature | -50°C to +80°C |
| Maximum Installation Altitude | 2000 m |
| Relative Humidity | 10–95% |
| Approximate Weight | 0.38 kg |
| Mounting | DIN Rail Mounting |
| Application | Motor Overload and Short-Circuit Protection |
No reviews yet.