Siemens 5SY6520-8CC High Current Double Pole Motor Circuit Breaker 1P+N 20A

The Siemens 5SY6520-8CC is a high-performance, double-pole motor circuit breaker engineered for robust protection of electrical circuits, particularly those powering motors. This 1P+N (1 pole + neutral) device offers a rated current of 20A and is designed to deliver superior safety, reliability, and operational efficiency in demanding industrial environments. Its advanced tripping characteristics ensure precise overload and short-circuit protection, safeguarding valuable equipment and preventing costly downtime. With its compact design and high breaking capacity, the 5SY6520-8CC is a critical component for modern electrical installations requiring dependable motor control and protection.

Siemens 5SY6520-8CC: Product Specifications

| Feature                 | Specification                               |

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

| Product Type            | Motor Circuit Breaker                       |

| Model Number            | 5SY6520-8CC                                 |

| Poles                   | Double Pole (1P+N)                          |

| Rated Current (Ie)      | 20A                                         |

| Rated Voltage (Ue)      | 400V AC                                     |

| Breaking Capacity (Icn) | 10kA                                        |

| Tripping Characteristic | Curve C                                     |

| Frequency               | 50/60 Hz                                    |

| Protection              | Overload, Short-Circuit, Thermal Magnetic |

| Mounting Type           | DIN Rail                                    |

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

| Protection Class        | IP20                                        |

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

Core Features & Market Positioning

The Siemens 5SY6520-8CC distinguishes itself through its robust construction and adherence to stringent international standards, positioning it as a premium solution for critical motor protection applications. Its Type C tripping curve is specifically optimized for inductive loads, such as motors, providing a balance between sensitive overload protection and the high inrush currents typical during motor start-up. This ensures reliable operation without nuisance tripping, a key differentiator in industrial settings where operational continuity is paramount. The double-pole design with neutral disconnect offers enhanced safety by isolating both live conductors and the neutral, a crucial feature for many motor control circuits. The high breaking capacity of 10kA assures that the breaker can safely interrupt fault currents, preventing damage to downstream equipment and mitigating electrical hazards.

Key Application Scenarios

This motor circuit breaker is ideally suited for protecting single-phase and three-phase motors in a wide array of industrial and commercial applications. Its precise 20A rating makes it perfect for controlling and safeguarding smaller to medium-sized electric motors used in pumps, fans, conveyors, and various types of machinery. It is a vital component in control panels and electrical distribution systems where reliable isolation and protection of motor loads are essential. Industries such as manufacturing, food and beverage processing, water treatment, and HVAC systems frequently specify Siemens circuit breakers like the 5SY6520-8CC for their durability and performance in environments with fluctuating electrical conditions.

Practical System Integration Guidance

Integrating the Siemens 5SY6520-8CC into existing electrical systems is straightforward, owing to its standard DIN rail mounting and conventional terminal design. Ensure that the incoming power supply lines and the outgoing load wires are connected to the appropriate terminals, observing correct polarity for the 1P+N configuration. The breaker should be installed in a clean, dry environment within an appropriate enclosure to maintain its IP20 protection rating. Proper torque should be applied to the terminals to ensure secure connections and prevent overheating. For systems requiring remote signaling of breaker status, auxiliary contacts (sold separately) can be easily attached to the side of the unit, facilitating integration with building management systems or PLCs for enhanced monitoring and control.

Operation and Risk Mitigation

The Siemens 5SY6520-8CC operates automatically, providing continuous protection against overloads and short circuits. The thermal element responds to sustained overcurrents, while the magnetic element provides instantaneous trip action for high fault currents, ensuring rapid disconnection of power to prevent damage. To mitigate risks, always ensure the breaker is rated appropriately for the motor's full load current and the supply voltage. Never bypass or defeat the protective mechanisms. In case of a trip, identify the cause of the fault before resetting the breaker; persistent tripping indicates an underlying issue requiring professional diagnosis. Regular visual inspection for signs of wear or damage is also recommended as part of a proactive maintenance schedule.

Scalability & Long-Term Value

The Siemens 5SY6520-8CC offers excellent long-term value due to its robust design and compatibility with Siemens' broader range of industrial control and automation products. While this specific unit is rated for 20A, Siemens provides a comprehensive portfolio of motor circuit breakers and protective devices that can accommodate higher current ratings and different pole configurations, allowing for system expansion or upgrades as operational needs evolve. Its adherence to international standards ensures compatibility with components from other reputable manufacturers. Furthermore, its reliable performance minimizes the likelihood of equipment failure, thereby reducing maintenance costs and extending the operational lifespan of connected machinery, contributing to overall system reliability and return on investment.

Frequently Asked Questions

1. What is the primary function of a Siemens 5SY6520-8CC?

This breaker protects electrical circuits and motors from damage. It offers overload and short-circuit protection.

It ensures operational safety and prevents equipment failure. The 20A rating is suitable for specific motor sizes.

The double-pole design isolates live and neutral, enhancing safety. It's a crucial component for reliable motor control.

2. How do I correctly wire the Siemens 5SY6520-8CC?

Connect incoming power to the designated line terminals. Route the load wires to the output terminals.

Observe correct polarity for the 1P+N configuration. Ensure secure connections by torquing terminals properly.

Consult the product manual for precise terminal identification and wiring diagrams. Always disconnect power before wiring.

3. What does the "C" in 5SY6520-8CC's tripping curve signify?

A "C" curve indicates it's designed for inductive loads like motors. It allows for higher inrush currents during startup.

This prevents nuisance tripping when motors start up. It provides a balance between protection and operational needs.

It trips between 5 to 10 times the rated current for short circuits. This is crucial for motor control applications.

4. Can the Siemens 5SY6520-8CC be used for single-phase and three-phase motors?

This specific model is a 1P+N breaker, suitable for single-phase loads. It can protect one phase and the neutral.

For three-phase motors, a three-pole or four-pole breaker is typically required. Ensure your motor's phase configuration matches the breaker.

Always verify the motor's power requirements and the available supply voltage against the breaker's specifications. Check the product datasheet for detailed application guidance.

5. What is the breaking capacity of the 5SY6520-8CC?

The breaking capacity (Icn) is 10kA. This indicates its ability to safely interrupt fault currents.

A high breaking capacity is essential for safety in industrial environments. It protects against severe short circuits.

This ensures the breaker can handle potential fault levels without failing. It's a critical safety parameter for circuit protection.

6. What are the typical applications for this motor circuit breaker?

It's used for protecting motors in pumps, fans, and conveyors. Manufacturing and HVAC sectors commonly use it.

It's integral to electrical control panels and distribution systems. Ensures reliable operation of industrial machinery.

Its 20A rating suits small to medium-sized motor loads. Provides dependable protection in various industrial settings.

7. How does the thermal magnetic trip mechanism work?

The thermal element detects sustained overloads. It uses a bimetallic strip to trip the breaker.

The magnetic element reacts instantly to high fault currents. It provides rapid short-circuit protection.

Together, these mechanisms offer comprehensive protection against electrical faults. Ensuring safety and equipment longevity.

8. What are the environmental operating conditions for this breaker?

It operates within a temperature range of -25°C to +55°C. Suitable for many industrial environments.

The protection class is IP20, meaning it's protected against solid objects over 12.5mm. It requires installation in an enclosure.

Avoid exposure to moisture or corrosive atmospheres. Ensure proper ventilation to maintain performance.

9. What is the advantage of a double-pole (1P+N) breaker?

It disconnects both the live conductor and the neutral. This provides a higher level of safety in some circuits.

It ensures complete isolation of the circuit when tripped. Crucial for specific motor control or equipment configurations.

This is different from single-pole breakers that only switch the live line. Offering enhanced circuit protection.

10. Where can I find reliable information or support for the Siemens 5SY6520-8CC?

Refer to the official Siemens product datasheet and manuals. These provide detailed technical specifications.

Contact authorized Siemens distributors or technical support. They offer expert advice and assistance with selection.

Online industrial component suppliers often have product details and customer reviews. These resources can help with application queries.