Siemens 3VA1140-4EF32-0AA0 Motor Protection Molded Case Circuit Breaker 40A 3P 36kA

The Siemens 3VA1140-4EF32-0AA0 is a robust 40A, 3-pole molded case circuit breaker (MCCB) engineered for reliable motor protection. Boasting a breaking capacity of 36kA, this unit is designed to safeguard electrical systems from overcurrents and short circuits, ensuring operational continuity and equipment longevity in demanding industrial environments. Its advanced thermal-magnetic release mechanism provides precise tripping characteristics essential for motor applications.

Product Specifications

| Feature                 | Specification                                      |

| :---------------------- | :------------------------------------------------- |

| Product Type            | Molded Case Circuit Breaker (MCCB)                 |

| Model Number            | 3VA1140-4EF32-0AA0                                 |

| Rated Current (In)      | 40A                                                |

| Number of Poles         | 3P (Three-Pole)                                    |

| Breaking Capacity (Icu) | 36kA                                               |

| Release Type            | Thermal-Magnetic                                   |

| Tripping Characteristic | For motor protection                               |

| Connection Type         | Screw Terminals                                    |

| Mounting Type           | DIN Rail or Panel Mounting                         |

| Compliance Standards    | IEC 60947-2, IEC 60947-4-1                           |

| Operating Voltage       | Up to 415V AC                                      |

| Ambient Temperature     | -25°C to +70°C                                     |

Core Features & Market Positioning

The Siemens 3VA1140-4EF32-0AA0 distinguishes itself through its high breaking capacity of 36kA, offering superior protection against fault currents in high-demand industrial settings. Its thermal-magnetic trip unit is specifically calibrated for motor protection, providing reliable safeguarding against overload and short circuits, crucial for preventing motor damage and minimizing downtime. This MCCB is positioned as a dependable and cost-effective solution for safeguarding critical motor loads, integrating seamlessly into various industrial power distribution systems. The robust construction and adherence to international standards like IEC 60947 ensure long-term operational reliability and safety.

Key Application Scenarios

This Siemens MCCB is ideally suited for protecting individual motor circuits in manufacturing plants, pumping stations, and conveyor systems. It effectively guards against thermal overloads that can occur during start-up or continuous operation, as well as dangerous short circuits. Its application extends to protecting distribution boards, transformers, and cable feeders where a 40A, 3-pole protective device with a 36kA breaking capacity is specified. The breaker's precise tripping ensures that nuisance tripping is minimized, while still providing prompt disconnection under fault conditions, thereby maintaining the productivity of essential industrial equipment.

Practical System Integration Guidance

Integrating the Siemens 3VA1140-4EF32-0AA0 into existing electrical infrastructure is straightforward due to its standard DIN rail mounting capability and screw terminal connections. When wiring, ensure the load and supply conductors are securely fastened to the appropriate terminals to prevent loose connections, which can lead to overheating and failure. For motor protection applications, it's critical to set the thermal overload element according to the motor's full-load current (FLA) rating, typically between 100% and 125% of FLA, while the magnetic short-circuit trip is usually set at a higher multiple of FLA to allow for inrush current during motor start-up. Always consult the motor nameplate and local electrical codes for precise settings.

Operation and Risk Mitigation

Operating the Siemens 3VA1140-4EF32-0AA0 involves understanding its manual trip and reset functions. The clearly marked ON/OFF lever indicates the breaker's status. In the event of a trip, visual inspection of the lever position will confirm a fault has occurred. To reset, first identify and rectify the cause of the fault (overload or short circuit). After the fault is cleared, the breaker can be reset by moving the lever to the "OFF" position and then to the "ON" position. Risk mitigation is enhanced by regular inspection of terminals for tightness and ensuring the breaker is not exposed to conditions outside its rated environmental parameters. Never attempt to reset a breaker without addressing the underlying fault.

Scalability & Long-Term Value

The Siemens 3VA1140-4EF32-0AA0 is part of Siemens' broader 3VA molded case circuit breaker family, offering a degree of scalability through potential integration with other devices in the series. While this specific model is a fixed-mount unit, its reliable performance and adherence to international standards contribute to long-term value by minimizing the need for premature replacement. For enhanced system monitoring and control, particularly in modern industrial automation and IIoT initiatives, consider integration with upstream and downstream intelligent devices or gateways that can communicate operational status and trip events, enabling predictive maintenance and remote management.

Frequently Asked Questions

What is the breaking capacity of the Siemens 3VA1140-4EF32-0AA0?

This circuit breaker features a substantial breaking capacity of 36kA at its rated voltage. This ensures it can safely interrupt high fault currents without sustaining damage.

This high rating is critical for installations where short-circuit currents could potentially exceed lower-rated devices. It provides a significant safety margin.

The 36kA rating is crucial for compliance with many industrial electrical codes and standards, ensuring a safe and reliable power system.

How do I set the overload protection on the 3VA1140-4EF32-0AA0?

The thermal overload setting should be adjusted based on the motor's full-load ampere (FLA) rating, typically between 100% and 125% of FLA. Consult the motor's nameplate for its specific FLA.

Fine-tuning the thermal setting minimizes nuisance tripping while ensuring adequate protection against sustained overcurrents that can damage motor windings.

Refer to the Siemens 3VA series manual for detailed instructions on adjusting the thermal trip element, ensuring correct calibration for your motor.

Can the Siemens 3VA1140-4EF32-0AA0 be used for cable protection?

Yes, this MCCB is suitable for cable protection when its trip settings are appropriately configured for the cable's current-carrying capacity and fault withstand levels. Its 36kA breaking capacity is often sufficient for many cable feeder applications.

When used for cable protection, ensure the thermal and magnetic trip settings are coordinated with the cable's thermal limits and the system's prospective short-circuit current.

Always verify that the cable's ampacity and insulation's short-circuit withstand capability are adequately protected by the chosen breaker settings and its overall rating.

What is the difference between Icu and Ics for this breaker?

Icu (ultimate breaking capacity) is the maximum fault current the breaker can interrupt under specified test conditions without being destroyed. Ics (service breaking capacity) is the current it can interrupt and still be capable of further service.

For the 3VA1140-4EF32-0AA0, the Icu is 36kA. While the Ics is not explicitly stated, it is typically a fraction of Icu, allowing for re-use after a fault.

Understanding this distinction is vital for assessing the breaker's reliability after a fault event and ensuring continued safe operation.

What are the typical applications for this 40A 3-pole MCCB?

This breaker is commonly used for protecting individual motor circuits in various industrial machinery. It's also applied to protect control panels, distribution boards, and smaller transformers.

Its robust design and 36kA rating make it suitable for manufacturing facilities, HVAC systems, and water treatment plants where reliable motor control is paramount.

Key applications include safeguarding pumps, fans, conveyors, and other essential rotating equipment against electrical faults.

How is the Siemens 3VA1140-4EF32-0AA0 mounted?

This MCCB is designed for flexible mounting, commonly utilizing a standard 35mm DIN rail. It can also be mounted directly to a panel using appropriate hardware.

Ensure the mounting surface is clean, level, and capable of supporting the breaker's weight and mechanical stresses during operation.

Secure and proper mounting is essential for the breaker's mechanical integrity and reliable electrical connection to the system busbars or terminals.

What does "3P" signify on the Siemens 3VA1140-4EF32-0AA0?

"3P" indicates that the circuit breaker is a three-pole unit, meaning it can simultaneously interrupt all three phases of a three-phase electrical system. This is standard for motor protection and industrial power distribution.

Protecting all three phases is crucial for preventing phase imbalance and ensuring that motor windings are not subjected to damaging voltage differences during a fault.

Using a 3-pole breaker ensures complete isolation of the load from the power supply when tripped, enhancing safety during maintenance and fault conditions.

Is this breaker suitable for DC applications?

No, the Siemens 3VA1140-4EF32-0AA0 is specifically designed and rated for AC (Alternating Current) applications only. Using it in DC circuits can lead to arc instability and failure.

AC circuit breakers operate with different arc-quenching principles compared to DC breakers, making them unsuitable for direct current loads.

Always select circuit breakers that are explicitly rated for the type of current (AC or DC) and voltage present in your application to ensure safety and performance.

What is the operating temperature range for this breaker?

This circuit breaker is designed to operate reliably within an ambient temperature range of -25°C to +70°C. Adhering to this range ensures optimal performance and longevity.

Operating the breaker outside these specified temperature limits can affect its tripping characteristics and potentially lead to premature failure.

Ensure adequate ventilation around the breaker installation, especially in enclosed panels, to maintain the ambient temperature within the manufacturer's recommended range.

Where can I find the full technical datasheet for the 3VA1140-4EF32-0AA0?

You can typically find the comprehensive technical datasheet on the official Siemens Industry online portal or through authorized Siemens distributors' websites. A quick search for "Siemens 3VA1140-4EF32-0AA0 datasheet" will yield direct links.

The datasheet contains detailed specifications, dimensional drawings, wiring diagrams, and performance curves essential for proper selection, installation, and operation.

Always refer to the official datasheet for the most accurate and up-to-date technical information before and during the installation process.