Siemens 5SN6350-7CN MCB for Heavy Load Protection 3P 50A

The Siemens 5SN6350-7CN Miniature Circuit Breaker (MCB) is engineered for robust protection of heavy-load circuits. This three-pole, 50-amp device offers reliable safeguarding against overcurrents and short circuits, making it an essential component for industrial and commercial power distribution systems. Its design prioritizes safety, performance, and ease of integration, ensuring operational continuity and equipment longevity.

Product Specifications

| Specification                   | Value                               |

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

| Product Designation             | Miniature Circuit Breaker           |

| Model                           | 5SN6350-7CN                         |

| Number of Poles                 | 3P                                  |

| Rated Current                   | 50A                                 |

| Tripping Characteristic         | C                                   |

| Rated Voltage                   | 400V AC                             |

| Rated Short-Circuit Breaking Capacity | 6 kA (according to EN 60898-1)      |

| Insulation Voltage (Ui)         | 440V AC                             |

| Frequency                       | 50/60 Hz                            |

| Energy Limitation Class         | 3                                   |

| Mechanical Service Life         | 10,000 operating cycles             |

| Protection Class                | IP20 (with connected conductors)    |

| Conductor Cross-section (solid) | 0.75 mm² - 35 mm²                   |

| Conductor Cross-section (stranded) | 0.75 mm² - 35 mm²                   |

| Tightening Torque               | 2.5 - 3.5 N·m                       |

| Dimensions (H x W x D)          | 90 mm x 54 mm x 70 mm               |

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

| Operating Temperature           | -25°C to +55°C                      |

Core Features & Market Positioning

The Siemens 5SN6350-7CN MCB distinguishes itself through its robust construction and adherence to stringent international standards, including IEC/EN 60898-1 and IEC/EN 60947-2. As part of Siemens' SENTRON portfolio, it embodies the brand's commitment to providing high-quality, reliable electrical protection solutions tailored for demanding environments. The 'C' tripping characteristic signifies its suitability for applications with moderate inrush currents, such as inductive loads and motor circuits, common in heavy-duty industrial settings. Its breaking capacity of 6 kA, with higher ratings available in other variants, ensures it can safely interrupt fault currents, preventing damage to downstream equipment and safeguarding electrical installations. Market positioning is defined by its role as a dependable workhorse for industrial power distribution, offering a balance of performance, durability, and integration capabilities within Siemens' broader electrical system offerings.

Key Application Scenarios

This Siemens 5SN6350-7CN MCB is ideally suited for protecting heavy loads in industrial facilities, manufacturing plants, and commercial buildings where significant electrical demand is present. Its three-pole configuration makes it perfect for three-phase power distribution, commonly found in motor control circuits, large machinery, HVAC systems, and power distribution panels. In industrial applications with increased short-circuit vulnerability, the 5SN series, which includes this model, provides enhanced protection up to 15 kA in some variants, though this specific 6 kA model is robust for many heavy-load scenarios. It serves as a critical component in end-to-end protection concepts for industry and infrastructure, ensuring operational continuity and preventing costly downtimes.

Practical System Integration Guidance

Integrating the Siemens 5SN6350-7CN MCB into existing or new electrical systems is streamlined by its design features. The device accepts conductor cross-sections ranging from 0.75 mm² to 35 mm² for both solid and stranded conductors. Installation on standard DIN mounting rails is facilitated by its snap-on fixing system, allowing for quick removal without tools. The MCB features combined terminals at both the top and bottom for flexible wiring. For robust connections, a tightening torque of 2.5 to 3.5 N·m is recommended for the screw-type terminals. Optional accessories, such as auxiliary switches (e.g., 5ST30620MC) and fault signal contacts, can be easily integrated to expand functionality and provide remote status monitoring.

Operation and Risk Mitigation

The Siemens 5SN6350-7CN MCB operates on an electro-mechanical principle, utilizing thermal release for overload protection (delayed tripping) and magnetic tripping for short-circuit protection (instantaneous tripping). Its 'C' curve characteristic ensures it trips within a specific range of overcurrents, typically 5 to 10 times the rated current, providing appropriate protection for inductive loads without nuisance tripping. The device incorporates a trip-free mechanism, guaranteeing that the contacts will open upon tripping, even if the handle is held in the ON position, thereby enhancing safety. The IP20 protection class, applicable with connected conductors, means it is protected against solid objects greater than 12.5mm but not against water, necessitating installation within an enclosure for comprehensive protection. Proper installation and adherence to electrical codes are paramount for safe operation and to mitigate risks associated with electrical faults.

Scalability & Long-Term Value

The Siemens 5SN6350-7CN MCB offers significant long-term value through its compatibility with a wide range of Siemens SENTRON accessories and its integration into broader Siemens industrial automation and IIoT ecosystems. The ability to add auxiliary switches, fault signal contacts, shunt trips, and undervoltage releases allows for system expansion and advanced monitoring capabilities. This modularity ensures that electrical installations can be scaled to meet evolving demands. Furthermore, Siemens' commitment to product development and support ensures that components like the 5SN6350-7CN remain relevant and supported within advanced power management solutions, including those that leverage digital technologies for predictive maintenance and operational efficiency.

Frequently Asked Questions

Q1: What is the tripping characteristic of the Siemens 5SN6350-7CN MCB?

The Siemens 5SN6350-7CN MCB features a Type C tripping characteristic. This curve is designed for circuits with moderate inductive loads or motors. It provides protection against overcurrents typically between 5 to 10 times the rated current. This characteristic prevents nuisance tripping from normal inrush currents.

Q2: What is the breaking capacity of the Siemens 5SN6350-7CN MCB?

This MCB has a rated short-circuit breaking capacity of 6 kA according to EN 60898-1 standards. This means it can safely interrupt a fault current up to 6,000 amps. It is suitable for many industrial and commercial applications.

Q3: Can the Siemens 5SN6350-7CN MCB be used for DC applications?

The Siemens 5SN6350-7CN is primarily designed for AC voltage applications. While some Siemens MCBs can be used for DC, this specific model's technical specifications indicate it is rated for 400V AC. Always consult the product datasheet for DC suitability.

Q4: What is the maximum conductor size that can be connected to the Siemens 5SN6350-7CN MCB?

The MCB can accommodate conductor cross-sections from a minimum of 0.75 mm² up to a maximum of 35 mm². This applies to both solid and stranded conductors. Ensure proper termination for secure connections.

Q5: What are the dimensions of the Siemens 5SN6350-7CN MCB?

The dimensions of this three-pole MCB are approximately 90 mm in height, 54 mm in width, and 70 mm in depth. These dimensions ensure it fits standard distribution boards. Precise measurements can be found in the technical data sheet.

Q6: What type of loads is the Siemens 5SN6350-7CN MCB best suited for?

This MCB is ideal for heavy-load protection, particularly in three-phase systems. Its Type C characteristic makes it suitable for motor control, large lighting systems, and inductive loads commonly found in industrial and commercial settings.

Q7: Can auxiliary components be added to the Siemens 5SN6350-7CN MCB?

Yes, the Siemens 5SN6350-7CN MCB supports a range of modular accessories. These include auxiliary switches, fault signal contacts, and shunt trips. These enhance monitoring and control capabilities.

Q8: What standards does the Siemens 5SN6350-7CN MCB comply with?

The MCB complies with international standards such as IEC/EN 60898-1 and IEC/EN 60947-2. These standards ensure its safety and performance in electrical installations. Compliance is crucial for system reliability.

Q9: How is the Siemens 5SN6350-7CN MCB installed?

Installation involves mounting on a standard DIN rail, typically within a distribution board or enclosure. Connectors are clearly marked, and a recommended tightening torque should be applied to ensure secure electrical connections.

Q10: What is the energy limitation class of this MCB?

The Siemens 5SN6350-7CN MCB belongs to energy limitation class 3. This indicates its effectiveness in limiting the energy let through during a short circuit event, thus protecting downstream components. It meets strict safety requirements.