Siemens 5SN6220-7CN Miniature Circuit Breaker (MCB) 2P 20A

The Siemens 5SN6220-7CN Miniature Circuit Breaker (MCB) 2P 20A is a robust and reliable electrical protection device engineered for demanding industrial and commercial applications. This 2-pole, 20-amp circuit breaker offers superior overcurrent and short-circuit protection, ensuring the safety and operational integrity of electrical circuits. Key advantages include its high breaking capacity, excellent tripping characteristics, and durable construction designed for longevity. Its core features encompass a compact design, user-friendly toggle operation, and compliance with international safety standards, positioning it as a preferred choice for professionals seeking dependable circuit protection solutions. Technical parameters highlight its 230/400V rated voltage, 20A rated current, and a tripping curve of C, suitable for inductive loads.

Product Specifications

| Feature             | Specification                                |

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

| Product Type        | Miniature Circuit Breaker (MCB)              |

| Poles               | 2P (2-pole)                                  |

| Rated Current       | 20A                                          |

| Rated Voltage       | 230/400V AC                                  |

| Tripping Curve      | C                                            |

| Breaking Capacity   | 6 kA                                         |

| Frequency           | 50/60 Hz                                     |

| Mounting Type       | DIN Rail                                     |

| Protection Class    | IP20                                         |

| Operating Temperature | -25°C to +45°C                               |

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

| Color               | White/Grey                                   |

| Dimensions (H x W x D) | Approx. 88 mm x 35 mm x 70 mm (standard module) |

Core Features & Market Positioning

The Siemens 5SN6220-7CN MCB distinguishes itself through its exceptional breaking capacity of 6 kA, providing a high level of protection against severe short-circuit events, a critical differentiator in industrial settings where fault currents can be substantial. Its Type C tripping curve is specifically designed to handle moderate inrush currents common in inductive loads like motors and transformers, preventing nuisance tripping while still offering rapid response to overloads and short circuits. This combination of robust protection and tailored tripping characteristics makes it a highly competitive option for various industrial power distribution needs. Siemens' reputation for quality and reliability further bolsters the market position of this MCB, assuring users of consistent performance and a long operational lifespan.

Key Application Scenarios

This Siemens 5SN6220-7CN MCB is ideally suited for a wide array of industrial and commercial applications where reliable circuit protection is paramount. It is commonly deployed in main distribution boards, sub-distribution panels, and control cabinets for protecting circuits supplying machinery, lighting systems, and power outlets. Its application extends to protecting circuits with moderate inductive loads, such as those found in manufacturing plants, workshops, and building services. The 2-pole design ensures complete isolation of both live and neutral conductors, which is often a requirement for specific equipment or safety regulations.

Practical System Integration Guidance

Integrating the Siemens 5SN6220-7CN MCB into existing electrical systems is straightforward due to its standard DIN rail mounting and conventional terminal design. For installation, ensure the power supply to the circuit is completely isolated. The MCB is mounted by clipping it onto a standard 35mm DIN rail. Connect the incoming power supply (line and neutral) to the upper terminals, typically marked with "L" and "N" respectively, and the outgoing load conductors to the lower terminals. It is crucial to adhere to local electrical codes and wiring regulations, ensuring correct conductor sizing and termination torques for safe and reliable operation. The breaker's clear labeling and intuitive toggle mechanism facilitate easy operation and disconnection when maintenance or troubleshooting is required.

Operation and Risk Mitigation

The Siemens 5SN6220-7CN MCB operates automatically, interrupting the circuit when an overcurrent or short-circuit condition exceeds its calibrated thresholds. The primary risk mitigation lies in its inherent protective function, preventing equipment damage, fires, and electrical hazards. Proper operation is indicated by the toggle position: "ON" for a closed circuit, "OFF" for an open circuit. If the MCB trips, it indicates an overload or a fault downstream. To reset, first identify and rectify the cause of the trip (e.g., remove the overload, fix the short circuit). Then, move the toggle to the "OFF" position and firmly push it back to "ON". Avoid repeatedly resetting a breaker that continues to trip, as this can indicate a persistent fault requiring professional diagnosis.

Scalability & Long-Term Value

The Siemens 5SN6220-7CN MCB offers significant long-term value through its compatibility with the broader Siemens SENTRON system and adherence to international standards, ensuring seamless integration with other protection and switching devices. While MCBs themselves are not typically "upgraded" in a software sense, their modular design and extensive product portfolio within the Siemens range allow for easy replacement or the addition of further protection devices as electrical system requirements evolve. This inherent compatibility simplifies future expansions or modifications to electrical infrastructure, reducing potential retrofitting costs and ensuring continued operational efficiency and safety for years to come.

FAQs

What is the purpose of a Siemens 5SN6220-7CN MCB?

This MCB protects electrical circuits from overloads and short circuits. It automatically disconnects power when current exceeds safe limits. This prevents damage to equipment and wiring.

It acts as a critical safety device in industrial and commercial power systems. Its primary role is to interrupt fault currents rapidly. This minimizes the risk of electrical fires and damage.

The Siemens 5SN6220-7CN offers reliable, resettable protection. It ensures continuous operation by safeguarding against unexpected electrical disturbances.

What are the key technical specifications of the 5SN6220-7CN?

The Siemens 5SN6220-7CN is a 2-pole, 20A miniature circuit breaker. It operates at a rated voltage of 230/400V AC with a 6 kA breaking capacity.

It features a Type C tripping curve, suitable for loads with moderate inrush currents. The MCB is designed for standard 35mm DIN rail mounting and has an IP20 protection rating.

It complies with IEC/EN 60898-1 and IEC/EN 60947-2 standards, ensuring high safety and performance levels.

Where is the Siemens 5SN6220-7CN MCB typically used?

This MCB is widely used in industrial and commercial power distribution. It protects circuits in main and sub-distribution boards. Applications include safeguarding machinery and lighting circuits.

It is also suitable for protecting circuits with inductive loads, common in manufacturing and building services. Its 2-pole design offers complete circuit isolation.

The 5SN6220-7CN provides essential protection for power outlets and various electrical equipment. Its reliability makes it a preferred choice for professionals.

How does the tripping curve (Type C) affect its application?

A Type C tripping curve is designed for circuits with higher inrush currents. This includes inductive loads like motors and transformers. It allows for temporary current surges without tripping.

This characteristic prevents nuisance tripping during motor start-up or transformer energization. However, it still provides rapid protection against short circuits.

The 5SN6220-7CN's Type C curve balances sensitivity to faults with tolerance for normal operational surges. This is crucial for many industrial motor applications.

What is the breaking capacity (kA) of this MCB, and why is it important?

The Siemens 5SN6220-7CN has a breaking capacity of 6 kA. This is the maximum fault current it can safely interrupt without sustaining damage.

A higher breaking capacity is crucial in industrial settings where fault currents can be very high. It ensures the MCB can safely shut down the circuit during severe short circuits.

This 6 kA rating provides adequate protection for most standard commercial and industrial distribution circuits. It is a key indicator of the MCB's robustness and safety performance.

Can the Siemens 5SN6220-7CN MCB be used for DC circuits?

The Siemens 5SN6220-7CN is specifically designed and rated for AC (Alternating Current) circuits only. Using it on DC circuits can lead to unsafe operation.

DC circuits have different arc quenching characteristics than AC circuits. Standard AC MCBs may not be able to extinguish the DC arc effectively. This can lead to failure and safety hazards.

Always use MCBs that are explicitly rated for DC voltage and current when protecting DC circuits. Refer to manufacturer specifications for appropriate DC-rated devices.

What are the advantages of using a 2-pole MCB like the 5SN6220-7CN?

A 2-pole MCB simultaneously switches both the live and neutral conductors. This provides complete isolation of the circuit from the power supply. It enhances safety during maintenance or fault conditions.

This full isolation is often a requirement in specific industrial applications or for certain types of equipment. It ensures that no voltage remains on the load side when the breaker is OFF.

The 2-pole design is also beneficial for circuits where the neutral conductor carries current or is part of the protective system. It ensures protection and isolation for the entire circuit path.

How do I reset the Siemens 5SN6220-7CN after it trips?

First, identify and eliminate the cause of the trip, such as an overload or short circuit. Do not attempt to reset without addressing the fault.

To reset, firmly move the toggle lever to the "OFF" position. Then, push the lever back up to the "ON" position. Ensure it latches securely.

If the MCB trips again immediately, there is likely a persistent fault. Do not force it; seek professional assistance to diagnose and repair the issue.

What standards does the Siemens 5SN6220-7CN comply with?

The Siemens 5SN6220-7CN complies with international standards IEC/EN 60898-1. This standard covers general requirements for household and similar fixed electrical installations.

It also meets the requirements of IEC/EN 60947-2. This standard specifically addresses miniature circuit breakers used in industrial control equipment.

Compliance with these standards assures users of the MCB's safety, performance, and reliability for its intended applications.

Is this MCB compatible with other Siemens electrical components?

Yes, the Siemens 5SN6220-7CN is part of the Siemens SENTRON protection and switching devices portfolio. It is designed for seamless integration within this system.

This compatibility ensures that it can be easily combined with other Siemens components like residual current devices (RCDs), surge protection devices (SPDs), and contactors. This facilitates the creation of comprehensive electrical protection and control solutions.

Its modular design and adherence to industry standards make it broadly compatible with many other electrical installation components, simplifying system design and future expansions.