Siemens 5SY6404-7CC Miniature Air Circuit Breaker 4P 4A

The Siemens 5SY6404-7CC is a robust 4-pole, 4-amp miniature air circuit breaker designed for reliable overcurrent protection in demanding industrial environments. Engineered for high performance and safety, this breaker offers superior tripping characteristics and enhanced operational safety. Its compact design and advanced features make it an ideal choice for safeguarding electrical installations against short circuits and overloads, ensuring operational continuity and equipment longevity.

Product Specifications

| Feature                 | Specification                               |

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

| Product Type            | Miniature Air Circuit Breaker               |

| Manufacturer            | Siemens                                     |

| Series                  | 5SY6                                        |

| Number of Poles         | 4                                           |

| Rated Current (In)      | 4 A                                         |

| Rated Voltage (Ue)      | 400 V AC                                    |

| Breaking Capacity (Icn) | 10 kA                                       |

| Tripping Characteristic | C                                           |

| Frequency               | 50/60 Hz                                    |

| Mounting Type           | DIN Rail                                    |

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

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

| Connection Type         | Screw Terminals                             |

| Compliance Standards    | IEC/EN 60898-1, IEC/EN 60947-2              |

Core Features & Market Positioning

The Siemens 5SY6404-7CC distinguishes itself through its high breaking capacity of 10 kA, providing robust protection against severe short-circuit events, a critical factor in industrial settings. Its Type C tripping characteristic is optimized for circuits with moderate inrush currents, such as those found with lighting and motor loads, offering sensitive yet reliable protection without nuisance tripping. This breaker is part of Siemens' extensive portfolio, known for its quality, reliability, and adherence to stringent international standards, positioning it as a preferred component for system integrators and electrical engineers prioritizing safety and performance. The 5SY series breakers are recognized for their durability and long service life, even under continuous operational stress.

Key Application Scenarios

This 4-pole, 4-amp circuit breaker is ideally suited for protecting main and distribution circuits in various industrial applications. It is commonly employed in control panels, machinery, and equipment where precise overcurrent protection is paramount. Specific use cases include safeguarding smaller motors, sensitive electronic equipment, and general power distribution within manufacturing plants, chemical processing facilities, and building management systems. Its suitability for 400V AC systems makes it a versatile choice for panel builders and maintenance engineers working with European and international power distribution standards.

Practical System Integration Guidance

Installation of the Siemens 5SY6404-7CC involves securely mounting it onto a standard 35mm DIN rail within an appropriate enclosure. The breaker features robust screw terminals designed for reliable connection of conductors up to 16 mm², ensuring secure electrical contact. Proper wiring of all four poles is essential for complete circuit protection. When integrating into control systems, ensure that the breaker's rated current and breaking capacity are well within the system's design parameters. Earthing and neutral connections should be made according to local electrical codes and manufacturer guidelines to maintain system integrity and safety.

Operation and Risk Mitigation

The Siemens 5SY6404-7CC operates automatically to interrupt electrical circuits when an overcurrent condition, such as a short circuit or overload, is detected, thereby preventing damage to connected equipment and mitigating fire hazards. Users should conduct regular visual inspections for any signs of damage or overheating. In the event of a trip, it is crucial to identify the cause of the overcurrent before resetting the breaker. Repeated tripping without an apparent cause may indicate an underlying system fault requiring professional diagnosis. Understanding the tripping characteristic (Type C) is vital for correct application and avoiding nuisance tripping during normal equipment startup.

Scalability & Long-Term Value

The 5SY6 series, including the 5SY6404-7CC, is designed for seamless integration within broader Siemens electrical infrastructure. While this specific breaker offers fixed protection ratings, its compatibility with other Siemens components, such as busbars, auxiliary switches, and remote signaling devices, allows for enhanced system functionality and monitoring capabilities. This compatibility ensures that as a facility's power requirements evolve, its protection infrastructure can be upgraded or expanded without compromising existing installations, thus offering long-term value and future-proofing electrical systems. Integration with digital monitoring solutions is possible through the addition of compatible accessories.

FAQs

Q1: What is the primary function of the Siemens 5SY6404-7CC breaker?

It interrupts electrical circuits during overcurrent events like overloads and short circuits. This protects downstream equipment from damage and prevents electrical fires.

This breaker ensures operational continuity by safeguarding sensitive components. It's a critical safety device in industrial and commercial power distribution.

The device's automatic tripping mechanism is key to its protective role. It operates based on thermal and magnetic tripping principles for precise protection.

Q2: What does "4P 4A" signify in the product name?

"4P" indicates that the circuit breaker has four poles, meaning it can switch all live conductors and the neutral in a three-phase system. "4A" denotes the rated current, which is 4 Amperes.

This combination is suitable for protecting circuits that require switching of all conductors simultaneously. It's essential for systems where neutral current needs to be interrupted.

The 4-pole design ensures complete isolation of the circuit when tripped. This is often required for specific safety standards or complex electrical configurations.

Q3: What is the breaking capacity of this circuit breaker?

The Siemens 5SY6404-7CC has a breaking capacity of 10 kA. This means it can safely interrupt fault currents up to 10,000 Amperes without being destroyed.

A high breaking capacity is crucial for industrial environments where short-circuit currents can be very large. It ensures the breaker can handle severe faults.

This specification guarantees reliable protection against catastrophic short circuits, preventing damage to the breaker and surrounding electrical infrastructure.

Q4: What is the significance of the "C" tripping characteristic?

A Type C tripping characteristic means the breaker will trip between 5 to 10 times its rated current. This is ideal for circuits with moderate inrush currents, such as motors or fluorescent lighting.

It provides a balance between sensitive overload protection and preventing nuisance tripping during normal equipment startup surges. This minimizes operational disruptions.

The Type C designation helps ensure that equipment like small motors can start up without tripping the breaker, while still offering robust protection against short circuits.

Q5: What type of electrical systems is the 5SY6404-7CC suitable for?

This breaker is designed for AC systems and is rated for 400V. It is commonly used in industrial and commercial power distribution networks operating at this voltage.

Its 4-pole configuration makes it suitable for three-phase systems where neutral switching is required. It adheres to international standards like IEC/EN 60898-1 and IEC/EN 60947-2.

The breaker's specifications make it a reliable choice for protecting circuits in manufacturing plants, control cabinets, and building electrical installations.

Q6: How is the Siemens 5SY6404-7CC installed?

Installation typically involves mounting the breaker onto a standard 35mm DIN rail within an electrical enclosure. Secure connections are made using the screw terminals.

Ensure all four poles are correctly wired according to the system's design and local electrical codes. Proper grounding and neutral connections are also critical.

Before installation, verify that the breaker's ratings (current, voltage, breaking capacity) are appropriate for the circuit being protected.

Q7: Can this breaker be used in residential applications?

While it meets IEC standards, the 5SY6404-7CC is primarily engineered for industrial and commercial use due to its specifications. Residential applications might use breakers with different pole configurations or breaking capacities.

Its 10 kA breaking capacity and 400V rating are more common in heavier industrial settings. Standard residential installations often use single-pole or double-pole breakers with lower ratings.

For residential use, it's always best to consult local electrical codes and use breakers specifically designed and rated for home environments.

Q8: What are the operating temperature limits for this breaker?

The Siemens 5SY6404-7CC operates reliably within an ambient temperature range of -25°C to +45°C. This wide range allows for use in various industrial environments.

Operating outside these temperature limits can affect the breaker's performance and lifespan. Extreme cold can impact tripping sensitivity, while excessive heat can lead to premature aging.

Ensure adequate ventilation within the enclosure where the breaker is installed, especially in warmer climates or enclosed control cabinets.

Q9: How do I reset the breaker after it trips?

To reset the breaker, first identify and rectify the cause of the trip (e.g., overload, short circuit). Then, simply push the lever back to the "ON" position.

If the breaker trips again immediately, do not force it. This indicates a persistent fault condition that requires professional inspection and repair.

Always ensure the circuit is safe before attempting a reset. Consult the product manual for specific reset procedures if unsure.

Q10: Does this breaker offer any protection against electric shock (shock protection)?

This miniature circuit breaker provides overcurrent protection, which indirectly contributes to safety by preventing dangerous fault currents. It does not, however, replace the need for RCDs (Residual Current Devices) for direct shock protection.

RCDs are specifically designed to detect small leakage currents to earth, which can indicate a person is receiving an electric shock. This breaker interrupts much larger fault currents.

For comprehensive safety, it is recommended to use this breaker in conjunction with appropriate RCDs, especially in circuits where direct contact with live conductors is a possibility.