Siemens 5SU9156-7KK16 RCCB Earth Leakage Protection Switch 16A 10mA 1P+N C

The Siemens 5SU9156-7KK16 is a vital component for ensuring electrical safety in a multitude of applications. This 16A, 10mA, 1-pole + neutral (1P+N) Residual Current Circuit Breaker (RCCB) with a Type C tripping characteristic offers robust earth leakage protection. Its key advantages include high sensitivity to small leakage currents, fast tripping response to prevent hazards, and reliable operation in various industrial and commercial environments. The 5SU9156-7KK16 is designed for DIN rail mounting, simplifying installation and maintenance.

Product Specifications

| Feature                 | Specification                                |

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

| Product Type            | Residual Current Circuit Breaker (RCCB)      |

| Manufacturer            | Siemens                                      |

| Model Number            | 5SU9156-7KK16                                |

| Rated Current (In)      | 16 A                                         |

| Rated Residual Current  | 10 mA                                        |

| Number of Poles         | 1P + N (1 Pole + Neutral)                    |

| Tripping Characteristic | Type C                                       |

| Rated Voltage (Un)      | 230 V AC                                     |

| Frequency               | 50/60 Hz                                     |

| Mounting Type           | DIN Rail                                     |

| Protection Class        | IP20                                         |

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

| Certifications          | VDE, CE                                      |

Core Features & Market Positioning

The Siemens 5SU9156-7KK16 distinguishes itself through its high-quality construction and adherence to stringent safety standards, making it a preferred choice for professionals seeking reliable earth leakage protection. Its 10mA sensitivity is crucial for protecting personnel against electric shock, especially in sensitive areas like healthcare facilities or those with increased risk. The Type C tripping characteristic provides reliable protection against overcurrents caused by inductive loads, such as motors, without causing nuisance tripping. This combination of sensitive earth leakage detection and robust overcurrent handling positions the 5SU9156-7KK16 as a versatile and dependable solution in the protective devices market.

Key Application Scenarios

This Siemens RCCB is ideally suited for protecting individual circuits in residential, commercial, and light industrial settings. Common applications include safeguarding circuits for lighting, socket outlets, and small appliances where the risk of earth faults is a primary concern. Its 16A rating makes it suitable for circuits with moderate power demands. Specifically, its 10mA sensitivity is highly beneficial in environments where direct contact with live parts is a possibility, such as workshops, laboratories, or areas with mobile equipment. The 1P+N configuration is efficient for single-phase systems, occupying only two modules on a standard DIN rail.

Practical System Integration Guidance

Integrating the Siemens 5SU9156-7KK16 into an electrical system is straightforward due to its standard DIN rail mounting design. Ensure the incoming live and neutral conductors are connected to the designated terminals, typically marked "L" and "N" respectively, ensuring correct polarity. The outgoing circuit conductors are then connected to the corresponding output terminals. For effective protection, the main incoming power supply to the distribution board must be properly earthed. The residual current device (RCD) functions by detecting an imbalance between the current flowing in the live conductor and returning through the neutral conductor. Any significant difference, indicating current leakage to earth, triggers the device to rapidly disconnect the circuit.

Operation and Risk Mitigation

The primary function of the Siemens 5SU9156-7KK16 is to detect earth leakage currents as low as 10mA. When such a current is detected, it operates within milliseconds, interrupting the circuit to prevent electric shock and potential fires. Regular testing of the RCCB using its integrated test button (usually labeled "T") is critical for ensuring its continued functionality. Pressing the test button simulates an earth fault, and if the device is operating correctly, it should trip, disconnecting the power. If the test fails, or if the device trips unexpectedly without a fault, it indicates a potential issue that requires professional inspection or replacement.

Scalability & Long-Term Value

As a component within a Siemens electrical installation system, the 5SU9156-7KK16 offers excellent compatibility with other Siemens circuit breakers, residual current devices (RCDs), and distribution board components. This ensures seamless integration and allows for the creation of comprehensive protection schemes. While the 5SU9156-7KK16 itself is a fixed-specification device, its value lies in its reliable, long-term performance, contributing to the overall safety and operational integrity of the electrical system. For applications requiring more advanced monitoring or integration with building management systems, Siemens offers a broader range of intelligent devices and solutions that can be part of a larger, scalable electrical infrastructure.

Frequently Asked Questions

What is the primary function of the Siemens 5SU9156-7KK16?

It serves as a Residual Current Circuit Breaker (RCCB) for detecting earth leakage currents. It protects against electric shock by quickly disconnecting power.

This device offers 16A current handling and a highly sensitive 10mA leakage detection threshold. Its 1P+N configuration is suitable for single-phase circuits.

The 5SU9156-7KK16 is essential for enhancing electrical safety in homes, offices, and industrial settings.

Can the Siemens 5SU9156-7KK16 protect against overloads and short circuits?

No, this RCCB primarily protects against earth leakage faults. It does not offer direct overload or short-circuit protection.

For comprehensive protection, it must be used in conjunction with a Miniature Circuit Breaker (MCB) or fuse. The MCB handles overcurrents and short circuits.

An MCB rated appropriately for the circuit should be installed upstream or downstream, depending on the system design, to provide complete circuit protection.

What does the "10mA" rating signify on the Siemens 5SU9156-7KK16?

The "10mA" indicates the sensitivity of the device to earth leakage current. It will trip when current exceeding 10 milliamperes leaks to earth.

This low threshold is crucial for personnel protection, as 10mA is generally considered the level at which electric shock can cause severe harm or become fatal.

A 10mA RCCB is typically used for supplementary protection on circuits with a higher risk of shock, such as those in wet areas or accessible by the public.

What is the meaning of "1P+N" on the Siemens 5SU9156-7KK16?

"1P+N" signifies that the device has one protected pole (live wire) and includes a neutral pole. It's a single-phase device.

This configuration ensures that both the live and neutral conductors are switched when a fault is detected, providing complete isolation.

It's designed for single-phase electrical installations, commonly found in residential and commercial buildings for lighting and power circuits.

What does the "Type C" tripping characteristic mean for the Siemens 5SU9156-7KK16?

"Type C" refers to the overcurrent tripping characteristic of the device. It's designed to tolerate higher inrush currents without tripping.

This characteristic is ideal for circuits with inductive loads, like motors or transformers, which experience temporary high current when starting up.

A Type C breaker will trip between 5 to 10 times its rated current, balancing protection against nuisance tripping from normal operational surges.

How do I install the Siemens 5SU9156-7KK16?

Install the 5SU9156-7KK16 onto a standard 35mm DIN rail within an electrical enclosure. Ensure the enclosure is properly ventilated and accessible.

Connect the incoming live and neutral conductors to the designated input terminals (usually marked L-in and N-in). The outgoing conductors for the protected circuit connect to the output terminals.

Always ensure the main power supply is switched off before commencing any installation work. Proper earthing of the system is paramount for the RCCB's correct operation.

How often should I test the Siemens 5SU9156-7KK16?

It is recommended to test the RCCB monthly using its built-in test button. This verifies the internal mechanism and tripping function.

Press the "T" button. The device should immediately trip, indicating proper operation. If it doesn't trip, or trips unexpectedly, it needs immediate inspection or replacement.

Regular testing ensures the device will perform as expected in a real earth leakage fault scenario, thus maintaining crucial safety standards.

What are the environmental conditions for operating the Siemens 5SU9156-7KK16?

The Siemens 5SU9156-7KK16 is designed for operation within an ambient temperature range of -25°C to +45°C.

It should be installed in a dry environment, protected from excessive dust, moisture, or corrosive substances. Its IP20 rating indicates protection against solid objects larger than 12.5mm.

Avoid exposing the device to extreme temperatures or environments that could compromise its electrical or mechanical integrity.

What is the rated voltage and frequency for this RCCB?

The Siemens 5SU9156-7KK16 is rated for a nominal voltage of 230V AC. This is standard for single-phase circuits in most regions.

It is designed to operate reliably at standard power frequencies of 50 Hz or 60 Hz. Ensure your supply frequency matches these specifications for optimal performance.

Using the device outside of its specified voltage and frequency range can lead to malfunction or permanent damage.

What is the physical size and module width of the Siemens 5SU9156-7KK16?

The 5SU9156-7KK16 occupies two standard modules on a 35mm DIN rail. This is a common size for single-phase protective devices.

Each module typically measures 18mm in width, so this RCCB will take up approximately 36mm of space on the rail. This allows for compact panel building.

Its compact design facilitates efficient use of space within electrical distribution boards and enclosures, especially when protecting multiple circuits.