Siemens 5SU9346-1CN50 RCBO Earth Leakage & Overcurrent Protector 50A 30mA 4P C

The Siemens 5SU9346-1CN50 RCBO is a sophisticated 4-pole Earth Leakage and Overcurrent Protector designed for robust electrical safety in demanding industrial and commercial environments. This unit provides simultaneous protection against overcurrents (short circuit and overload) and residual currents, safeguarding personnel and equipment from electrical hazards. Its compact design, high breaking capacity, and precise tripping characteristics make it an ideal solution for critical power distribution applications where reliability and safety are paramount. Key technical parameters include a 50A rated current, 30mA residual current sensitivity, and a Type C tripping curve, ensuring optimal protection for inductive loads.

Product Specifications

| Feature                    | Specification                               |

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

| Product Type               | RCBO (Residual Current Breaker with Overcurrent) |

| Manufacturer               | Siemens                                     |

| Model Number               | 5SU9346-1CN50                               |

| Number of Poles            | 4                                           |

| Rated Current (In)         | 50A                                         |

| Residual Current (IΔn)     | 30mA                                        |

| Tripping Characteristic    | Type C                                      |

| Rated Voltage (Un)         | 400V AC                                     |

| Rated Breaking Capacity (Icn) | 10kA                                        |

| Frequency                  | 50/60 Hz                                    |

| Terminal Type              | Screw Terminals                             |

| Mounting Type              | DIN Rail                                    |

| Protection Class           | IP20                                        |

Core Features & Market Positioning

The Siemens 5SU9346-1CN50 stands out in the market due to its integrated protection capabilities, reducing the need for separate overcurrent and residual current devices, thereby saving panel space and installation time. Its Type C tripping curve is specifically engineered to handle inrush currents associated with inductive loads, such as motors and transformers, without nuisance tripping. This intelligent design, combined with Siemens' reputation for quality and reliability, positions the 5SU9346-1CN50 as a premium choice for engineers and specifiers prioritizing superior electrical protection and operational continuity. The 10kA breaking capacity ensures it can safely interrupt fault currents even in high-power distribution systems.

Key Application Scenarios

This RCBO is ideally suited for protecting circuits in industrial machinery, control panels, and commercial building distribution boards where a combination of overcurrent and earth leakage protection is mandated. Specific applications include safeguarding motors, pumps, HVAC systems, and lighting circuits from both overload conditions and dangerous earth faults. Its 4-pole configuration is essential for IT, TN-S, and TN-CS systems where protection of all conductors, including the neutral, is required. The 30mA sensitivity makes it suitable for personnel protection against electric shock.

Practical System Integration Guidance

Integrating the Siemens 5SU9346-1CN50 into existing or new electrical systems is straightforward, leveraging standard DIN rail mounting and accessible screw terminals for secure connections. Proper wiring is crucial: line conductors should be connected to the upper terminals (typically L1, L2, L3, and N from left to right) and load conductors to the lower terminals in the corresponding order. Ensure that the neutral conductor is also protected by passing through the device for effective 4-pole operation. Before energizing, verify all connections and confirm that the device is correctly latched onto the DIN rail. Always adhere to local electrical codes and standards during installation.

Operation and Risk Mitigation

The 5SU9346-1CN50 operates by continuously monitoring both the current flowing through the live conductors and the current returning through the neutral conductor. Any imbalance exceeding the 30mA residual current threshold, indicative of an earth fault, will trigger a rapid trip, disconnecting the circuit. Similarly, overloads or short circuits will cause the overcurrent protection element to trip. Risk mitigation is achieved through its reliable fault detection and interruption capabilities. In the event of a trip, identify the cause (overload, short circuit, or earth leakage) before resetting the device. Ensure the correct reset procedure is followed by firmly pushing the toggle switch upwards.

Scalability & Long-Term Value

The Siemens 5SU9346-1CN50 offers significant long-term value through its compatibility with the broader Siemens SENTRON protection device portfolio. This allows for seamless integration into larger electrical protection schemes and facilitates future system expansions or upgrades. Its robust construction ensures a long operational lifespan, minimizing the need for premature replacements. While not directly an IIoT device, its reliable performance contributes to the overall stability of a connected industrial system, indirectly supporting digital integration by preventing disruptions caused by electrical faults.

Frequently Asked Questions

What is the primary function of the Siemens 5SU9346-1CN50 RCBO?

This RCBO provides combined protection against overcurrents like overloads and short circuits. It also detects and interrupts circuits in the event of dangerous earth leakage faults.

This dual protection enhances safety for both personnel and electrical equipment from various fault conditions. Its 30mA sensitivity is specifically tuned for effective personal protection against electric shock.

The Siemens 5SU9346-1CN50 is a crucial component for preventing electrical fires and ensuring operational continuity in sensitive installations.

How does the Type C tripping curve benefit industrial applications?

The Type C characteristic allows for higher inrush currents without causing nuisance tripping. This is vital for inductive loads that temporarily draw more current upon startup.

Applications like motors, transformers, and fluorescent lighting systems benefit from this feature, ensuring stable operation. It prevents unnecessary downtime and service interruptions.

By accommodating these temporary surges, the 5SU9346-1CN50 maintains system reliability and operational efficiency in demanding industrial settings.

What type of electrical systems is the 4-pole configuration suitable for?

The 4-pole design is ideal for systems requiring protection of all conductors, including the neutral. This is common in IT, TN-S, and TN-CS earthing systems.

It ensures that the neutral conductor is disconnected simultaneously with the live conductors during a fault. This provides a higher level of safety, especially in systems with a grounded neutral.

Utilizing a 4-pole RCBO like the 5SU9346-1CN50 is essential for comprehensive fault protection and compliance with specific electrical system standards.

Can the Siemens 5SU9346-1CN50 be used for residential or only industrial settings?

While designed with industrial robustness, its 30mA sensitivity also makes it suitable for high-end residential or multi-unit dwellings. It offers superior protection for complex home electrical systems.

However, its 50A rating and 4-pole configuration are more typically specified for commercial or industrial power distribution panels. It meets stringent safety requirements in these environments.

For standard residential circuits, a 2-pole RCBO might be sufficient, but the 5SU9346-1CN50 provides an elevated level of safety and protection where needed.

What is the breaking capacity of the 5SU9346-1CN50 and why is it important?

The 5SU9346-1CN50 features a breaking capacity of 10kA. This indicates the maximum fault current it can safely interrupt without being damaged.

A higher breaking capacity is critical in systems where large fault currents are possible, such as near transformers or utility service entrances. It ensures safety during severe short-circuit events.

Selecting an RCBO with adequate breaking capacity prevents catastrophic failure, protecting the installation and ensuring personnel safety during fault conditions.

How do I reset the Siemens 5SU9346-1CN50 after it trips?

First, identify and rectify the cause of the trip, whether it's an overload, short circuit, or earth leakage. Never reset a device without addressing the fault.

To reset, firmly push the toggle switch to the "OFF" position, then push it fully to the "ON" position. The device should then remain engaged.

If the RCBO trips again immediately after resetting, it indicates the fault condition still exists and requires further investigation by a qualified electrician.

What is the role of the 30mA residual current sensitivity?

The 30mA threshold is crucial for detecting small earth leakage currents that pose a risk of electric shock to humans. It triggers a rapid disconnection to prevent injury.

This sensitivity level is the standard for personal protection devices in many electrical codes worldwide. It ensures safety in areas where contact with live parts is possible.

By limiting leakage current, the 5SU9346-1CN50 significantly reduces the danger of electrocution, making it a vital safety feature.

Is the Siemens 5SU9346-1CN50 compatible with other brands of circuit protection devices?

While it can be installed in a panel containing other brands, it is recommended to use Siemens' own busbars and accessories for optimal compatibility and performance.

Mixing brands for busbar connections or wiring accessories can sometimes lead to issues with fit, reliability, or safety compliance. Siemens devices are designed to work seamlessly within their ecosystem.

For guaranteed safety and performance, adhering to a single manufacturer's components, especially for critical protection devices, is best practice.

What are the typical physical dimensions and mounting requirements?

The Siemens 5SU9346-1CN50 is designed for standard DIN rail mounting (35mm). It occupies a specific number of modular units (typically 4 modules wide for a 4-pole device).

Its compact design ensures efficient use of space within electrical enclosures and distribution boards. Precise dimensions are available in the technical datasheets.

Ensure adequate clearance and ventilation around the installed device as per electrical installation guidelines.

Where can I find the detailed technical datasheet for the Siemens 5SU9346-1CN50?

Official Siemens product documentation, including detailed technical datasheets, is typically available on the Siemens Industry Online Support (SIOS) portal. You can also find them on authorized Siemens distributor websites.

These datasheets provide comprehensive information on electrical characteristics, dimensions, installation instructions, and certifications. They are essential for proper system design and integration.

Always refer to the latest version of the datasheet to ensure you have the most accurate and up-to-date technical specifications for your application.