Siemens 5SV3644-4 Miniature Circuit Breaker 4P 40A 300mA

The Siemens 5SV3644-4 Miniature Circuit Breaker is a robust four-pole device designed for superior electrical protection in demanding industrial and commercial environments. This 40A, 300mA residual current circuit breaker (RCCB) offers enhanced safety through reliable tripping mechanisms and advanced switching technology. Its key advantages lie in its high breaking capacity, swift fault current interruption, and compliance with stringent international safety standards, making it an ideal choice for safeguarding circuits against overloads, short circuits, and dangerous earth leakage currents. Core features include a modular design for easy installation, clear status indication, and a durable construction built for longevity.

| Parameter               | Specification                       |

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

| Product Type            | Miniature Circuit Breaker (MCB)     |

| Number of Poles         | 4                                   |

| Rated Current (In)      | 40 A                                |

| Residual Current (IΔn)  | 300 mA                              |

| Tripping Characteristic | Type A (sensitive to AC and pulsating DC) |

| Breaking Capacity (Icn) | 6 kA                                |

| Voltage Rating          | 400 V AC                            |

| Frequency               | 50/60 Hz                            |

| Terminal Type           | Screw Terminal                      |

| Mounting Type           | DIN Rail                            |

| Protection Class        | IP20 (device), IP40 (enclosure)     |

| Operating Temperature   | -25°C to +45°C                      |

| Certifications          | IEC/EN 61009-1, IEC/EN 60947-2      |

Core Features & Market Positioning

The Siemens 5SV3644-4 distinguishes itself with its Type A tripping characteristic, offering protection against AC and pulsating DC fault currents, a critical differentiator in applications where such fault types are prevalent. This advanced sensitivity, coupled with a robust 6 kA breaking capacity, positions it as a premium protective device capable of handling significant fault energy, thereby minimizing damage and downtime. Its industrial-grade construction ensures reliable operation even under harsh environmental conditions, a testament to Siemens' legacy in electrical engineering.

Key Application Scenarios

This 40A, 4-pole RCCB is ideally suited for main distribution boards and sub-distribution systems in industrial facilities, commercial buildings, and demanding residential complexes. Its primary role is to provide protection for circuits supplying heavy machinery, control panels, and multiple power outlets where the risk of earth leakage is higher. Applications include protecting circuits in manufacturing plants, workshops, data centers, and any scenario requiring reliable discrimination between residual currents and nuisance tripping, particularly when dealing with electronic equipment.

Practical System Integration Guidance

Installation of the Siemens 5SV3644-4 is streamlined due to its DIN rail mounting compatibility and standard terminal connections. Ensure the main power supply is de-energized before commencing any work. Connect the incoming phase and neutral conductors to the designated top terminals, and the outgoing protected circuit conductors to the corresponding bottom terminals. Proper grounding of the enclosure and associated equipment is paramount for effective residual current protection. The device's modular design allows for straightforward integration into existing or new Siemens distribution boards and enclosures.

Operation and Risk Mitigation

The 5SV3644-4 operates by continuously monitoring the current flowing through the live and neutral conductors. If an imbalance exceeding 300mA is detected, indicating current leakage to earth, the breaker will rapidly trip, interrupting the circuit and preventing electrical shock hazards. To mitigate risks, regular testing of the residual current function using the integrated test button (typically labeled "T") is recommended. This ensures the device remains operational and can effectively provide life-saving protection. Fault tripping is visually indicated by the position of the toggle lever.

Scalability & Long-Term Value

Siemens' commitment to backward and forward compatibility within its electrical distribution systems enhances the long-term value of the 5SV3644-4. It integrates seamlessly with other components from the Siemens low-voltage product portfolio, allowing for flexible system design and future expansion. While not directly an IIoT device, its reliable performance contributes to the overall stability and safety of connected industrial systems, indirectly supporting digital transformation initiatives by ensuring a secure power foundation.

Frequently Asked Questions (FAQs)

1. What is the primary function of a Siemens 5SV3644-4 circuit breaker?

This device acts as a residual current circuit breaker (RCCB). It protects electrical circuits from faults caused by earth leakage. Its main purpose is to prevent electric shocks and fires.

Its four poles offer protection for three-phase systems or single-phase circuits requiring neutral protection. The 40A rating makes it suitable for circuits with significant power loads.

The 300mA sensitivity is designed for fire protection and enhanced safety in commercial and industrial settings. It's a vital safety component in modern electrical installations.

2. What types of faults can the Siemens 5SV3644-4 detect and interrupt?

It is primarily designed to detect and interrupt residual currents. These are imbalances between live and neutral conductors. Such imbalances typically indicate current leaking to earth.

The Type A characteristic means it can detect both AC and pulsating DC residual currents. This is crucial for modern installations with electronic equipment. It offers broader protection than Type AC breakers.

In addition to earth leakage, like any circuit breaker, it also provides protection against overcurrents and short circuits due to its integrated overcurrent protection elements.

3. How does the 40A and 300mA rating influence the application of this breaker?

The 40A rating signifies the maximum continuous current the breaker can handle without tripping due to overload. This makes it suitable for circuits feeding substantial loads.

The 300mA residual current sensitivity is generally used for fire protection and supplementary protection. It's higher than the 30mA typically used for personal protection.

This combination makes it ideal for main distribution points or circuits where substantial power is consumed and fire risk mitigation is a priority.

4. Can the Siemens 5SV3644-4 be used in residential or solely industrial applications?

While designed with industrial robustness, its protective features are also highly valuable in advanced residential applications. It can be used in main distribution panels of larger homes or multi-unit dwellings.

Its four-pole configuration is less common in standard residential single-phase setups but is essential for three-phase power or specific circuits requiring neutral isolation.

The 300mA rating is more typical for supplementary protection or fire prevention in non-dwelling buildings like offices or workshops.

5. What are the key safety benefits of installing this specific Siemens RCCB?

It significantly reduces the risk of electric shock to personnel. By quickly interrupting fault currents, it prevents dangerous current flow through the human body.

It also provides crucial fire protection. Earth leakage currents, especially under load, can generate heat and ignite surrounding materials. This breaker mitigates that risk.

The reliable tripping mechanism ensures that safety is maintained even in demanding environments, offering peace of mind and compliance with safety standards.

6. How is the Siemens 5SV3644-4 installed and wired?

Installation involves clipping the breaker onto a standard 35mm DIN rail. Ensure the rail is securely mounted within a suitable enclosure.

Wiring requires connecting the incoming power lines (phase(s) and neutral) to the top terminals and the outgoing circuit conductors to the bottom terminals. Correct polarity is essential.

Always ensure the power supply is completely disconnected and locked out before attempting any wiring or maintenance work. Consult the manual for detailed wiring diagrams.

7. What does the "4P" designation mean for this Siemens breaker?

"4P" stands for four poles. This means the breaker has four independent switching contacts. It is designed for circuits that require switching or protection of all four conductors.

These typically include three-phase systems (L1, L2, L3, N) or specific single-phase applications where switching the neutral is also required for complete isolation.

Having four poles ensures complete disconnection of the circuit, enhancing safety and facilitating maintenance by fully isolating the load.

8. How can I test the functionality of the 5SV3644-4?

Most Siemens RCCBs, including this model, feature a built-in test button, often labeled "T". Periodic manual testing is crucial for verifying operational readiness.

Pressing the test button simulates an earth fault condition. If the breaker is functioning correctly, it should trip immediately, interrupting the circuit.

If the breaker does not trip when the test button is pressed, it indicates a malfunction, and the device must be replaced immediately to ensure safety.

9. What is the breaking capacity (Icn) of 6 kA, and why is it important?

The breaking capacity (Icn) indicates the maximum fault current the circuit breaker can safely interrupt without being destroyed. A 6 kA rating signifies a substantial capability.

This means the 5SV3644-4 can safely disconnect circuits experiencing significant short-circuit currents up to 6,000 Amperes. This prevents catastrophic damage to the breaker and connected equipment.

A higher breaking capacity ensures greater protection and reliability, especially in industrial settings where fault currents can be considerably higher than in residential areas.

10. Is this breaker compatible with Siemens' wider range of electrical distribution products?

Yes, Siemens designs its low-voltage components for seamless integration. The 5SV3644-4 is compatible with various Siemens enclosures and busbar systems.

This compatibility allows for flexible design and expansion of electrical distribution boards. It simplifies the process of building or upgrading electrical infrastructure.

By using components from the same manufacturer, users can ensure optimal performance and maintain warranty integrity for their electrical systems.