Siemens 5SY6425-7CC Industrial Miniature Circuit Breaker 4P 25A

The Siemens 5SY6425-7CC is a robust 4-pole, 25A miniature circuit breaker (MCB) designed for demanding industrial environments. This device offers superior protection against overcurrents and short circuits, ensuring the safety and reliability of electrical installations. Its key advantages include high breaking capacity, enhanced safety features, and seamless integration into existing Siemens electrical systems. The 5SY6425-7CC boasts a rated breaking capacity of 25 kA, fulfilling IEC 60898-1 and IEC 60947-2 standards, and operates efficiently within a temperature range of -40°C to +70°C.

Siemens 5SY6425-7CC: Product Specifications

| Feature                   | Specification                                 |

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

| Product Type              | Miniature Circuit Breaker (MCB)               |

| Manufacturer              | Siemens                                       |

| Series                    | 5SY6                                          |

| Number of Poles           | 4                                             |

| Rated Current (In)        | 25 A                                          |

| Rated Voltage (Ue)        | 400/415 V AC                                  |

| Rated Insulation Voltage  | 500 V                                         |

| Rated Breaking Capacity   | 25 kA (IEC 60898-1, IEC 60947-2)              |

| Tripping Characteristic   | C                                             |

| Frequency                 | 50/60 Hz                                      |

| Ambient Temperature Range | -40°C to +70°C                                |

| Mounting Type             | DIN rail (35 mm)                              |

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

| Terminal Type             | Screw terminals                               |

| Wire Cross-Section        | 1.5 to 35 mm² (solid), 1.5 to 25 mm² (stranded) |

Core Features & Market Positioning

The Siemens 5SY6425-7CC distinguishes itself through its high performance and unwavering reliability, making it a preferred choice for critical industrial applications. Its 'C' tripping characteristic is optimized for inductive loads, providing a balance between overload protection and preventing nuisance tripping from inrush currents common in motors and transformers. This MCB is built to withstand harsh industrial conditions, offering robust mechanical and electrical endurance. As part of Siemens' extensive portfolio of low-voltage protection devices, it ensures seamless compatibility and integration within broader Siemens electrical infrastructure, a significant advantage for facilities already standardized on Siemens components.

Key Application Scenarios

This 4-pole, 25A circuit breaker is ideally suited for protecting main distribution boards and sub-distribution boards in industrial settings. It excels in safeguarding circuits with high inrush currents, such as those powering motors, pumps, and compressors in manufacturing plants. Its suitability extends to protecting power supplies for control systems, HVAC equipment, and large machinery where consistent and reliable power is paramount. The 25 kA breaking capacity ensures it can safely interrupt fault currents even in complex industrial power networks, providing essential protection for personnel and equipment.

Practical System Integration Guidance

Installing the Siemens 5SY6425-7CC involves mounting it securely onto a standard 35mm DIN rail, a common practice in industrial control panels. Ensure the power source is de-energized before commencing any wiring. The device accommodates flexible and rigid conductors ranging from 1.5 to 35 mm² for solid wire and 1.5 to 25 mm² for stranded wire, utilizing robust screw terminals for secure connections. Correct wiring order is crucial: typically, line conductors are connected to the top terminals and load conductors to the bottom. Proper torque must be applied to the terminals to prevent overheating and ensure optimal electrical contact.

Operation and Risk Mitigation

The primary function of the Siemens 5SY6425-7CC is to interrupt electrical circuits automatically during overcurrent or short-circuit events, thereby preventing damage to electrical equipment and mitigating fire hazards. The 'C' curve tripping mechanism activates at 5 to 10 times the rated current, offering protection against moderate overloads and high inrush currents. In case of tripping, identify the cause of the fault (e.g., overloaded circuit, short circuit, equipment malfunction) before resetting the breaker. Repeated tripping indicates an underlying issue that requires professional diagnosis. Always follow local electrical codes and safety standards during operation and maintenance.

Scalability & Long-Term Value

The 5SY6 series, including the 5SY6425-7CC, integrates seamlessly with other Siemens low-voltage components, facilitating scalable and adaptable electrical system designs. Its modular nature allows for straightforward expansion or modification of distribution boards. For facilities embracing Industry 4.0 initiatives, Siemens offers complementary devices and software solutions that can monitor the status and performance of circuit breakers, enabling predictive maintenance and optimizing operational efficiency. This backward and forward compatibility ensures long-term investment protection and facilitates future upgrades to more intelligent power management systems.

Frequently Asked Questions (FAQs)

What is the tripping characteristic of the Siemens 5SY6425-7CC?

The Siemens 5SY6425-7CC features a Type C tripping characteristic. This means it is designed to trip between 5 to 10 times its rated current.

This characteristic is ideal for inductive loads, accommodating higher inrush currents without causing nuisance tripping. It provides a balance for motor protection and similar applications.

Type C breakers are commonly used in industrial settings for circuits with equipment like motors, transformers, and fluorescent lighting.

What is the breaking capacity of the Siemens 5SY6425-7CC?

The Siemens 5SY6425-7CC has a rated breaking capacity of 25 kA. This is a significant fault current interruption capability.

A 25 kA rating ensures the breaker can safely and reliably interrupt short-circuit currents in most industrial power distribution systems. It meets stringent international standards like IEC 60898-1 and IEC 60947-2.

This high breaking capacity is critical for ensuring the safety of personnel and preventing damage to electrical infrastructure during severe fault conditions.

Can the Siemens 5SY6425-7CC be used for motor protection?

Yes, the Siemens 5SY6425-7CC is suitable for motor protection applications. Its Type C tripping curve is beneficial for handling motor inrush currents.

While it offers overload protection, for comprehensive motor protection against specific thermal and jam conditions, it's often used in conjunction with a motor starter or overload relay.

The 25A rating and 4-pole design make it appropriate for direct-on-line starting or as a main protective device for smaller to medium-sized motors.

What is the maximum voltage rating for the Siemens 5SY6425-7CC?

The Siemens 5SY6425-7CC has a rated voltage (Ue) of 400/415 V AC. This is standard for industrial power distribution in many regions.

It also has a rated insulation voltage of 500V, indicating its capability to withstand electrical stress between conductors. Always ensure the system voltage does not exceed these specifications.

The 4-pole design allows for the switching of all three phases plus the neutral conductor, which is essential for certain types of industrial equipment and power systems.

What is the operating temperature range for this MCB?

The Siemens 5SY6425-7CC can operate reliably within an ambient temperature range of -40°C to +70°C. This wide range is characteristic of industrial-grade equipment.

This broad operating temperature makes it suitable for installation in diverse environments, from very cold to very hot conditions, without compromising performance.

However, extreme temperatures or continuous operation at the upper limit may affect the breaker's current-carrying capacity or lifespan, so derating might be considered.

How do I wire the Siemens 5SY6425-7CC?

Wiring involves securely mounting the MCB on a 35mm DIN rail and connecting conductors to the screw terminals. Typically, input power connects to the top terminals and output to the bottom.

The breaker accepts solid wires from 1.5 to 35 mm² and stranded wires from 1.5 to 25 mm². Ensure proper stripping of insulation and use appropriate torque for secure connections.

Always de-energize the circuit before wiring and double-check connections for correctness and tightness to prevent faults and ensure safety.

What does "4P" mean in the product name?

"4P" in the Siemens 5SY6425-7CC designation stands for 4-pole. This means the circuit breaker has four separate poles or circuits that it can interrupt.

A 4-pole breaker simultaneously switches all three live phases and the neutral conductor. This is crucial for certain types of equipment and earthing systems, especially in IT or TN-S systems requiring neutral switching.

It provides complete isolation of the circuit when tripped, enhancing safety and allowing for maintenance on connected equipment.

What is the significance of the "C" in the tripping characteristic?

The "C" signifies a Type C circuit breaker. This tripping characteristic is designed for loads with moderate inrush currents.

It will trip between 5 to 10 times its rated current (25A in this case). This prevents nuisance tripping from the brief current surge when starting motors or switching on transformers.

This makes it suitable for circuits supplying inductive loads, providing effective protection against overloads and short circuits while minimizing unwanted interruptions.

Where is the Siemens 5SY6425-7CC typically used in an industrial setting?

This MCB is commonly found in industrial main distribution boards and sub-distribution panels. It's used to protect circuits supplying heavy machinery, motors, and pumps.

Its high breaking capacity makes it suitable for primary protection points in facilities where fault currents can be substantial. It ensures reliable power distribution for critical industrial processes.

It can also protect circuits for HVAC systems, large lighting installations, and control panels that require robust overcurrent protection.

What are the main safety features of this circuit breaker?

The primary safety feature is its automatic tripping mechanism, which interrupts the circuit during overcurrent or short-circuit faults to prevent fires and equipment damage. Its robust construction ensures reliability in demanding conditions.

The 4-pole design allows for complete isolation of all conductors (3 phases and neutral) when tripped, providing enhanced safety during maintenance. It adheres to international safety standards for electrical protection devices.

Correct installation, including proper wiring and terminal torquing, is essential for maintaining its safety integrity. Regular inspection and testing are also recommended in industrial environments.