When it comes to electrical enclosures, safety, performance, and compliance are paramount. One crucial component that often goes unnoticed but plays a vital role in achieving these goals is the separation plate. Let’s explore why separation plates are so significant in electrical enclosures and the different types available
Ensuring Electrical Isolation
- Insulation Barriers: Separation plates act as physical and dielectric barriers, maintaining electrical isolation between components operating at different voltage levels. This prevents accidental contact and potential short circuits, which can cause serious issues
- Clearance and Creepage Distances: By helping maintain necessary clearance (air gap) and creepage (surface distance) distances as per standards like IEC 60664, separation plates play a critical role in preventing electrical arcing.
Managing Electromagnetic Compatibility (EMC)
- Reducing Electromagnetic Interference (EMI): High-frequency components like power supplies and inverters can generate a lot of noise. Separation plates help keep these noisy components away from sensitive control circuits like PLCs, thereby reducing EMI.
- Shielding: Acting as an additional shield, separation plates help in mitigating radiated EMI.
Improving Thermal Management
- Heat Dissipation Control: Separation plates guide airflow within the enclosure, enhancing the effectiveness of cooling systems and preventing hotspots by directing heat away from critical components.
- Creating Thermal Zones: By establishing distinct thermal zones, separation plates ensure that heat-generating components do not adversely affect the performance of heat-sensitive components, maintaining operational reliability. However, it is important to note that perforated separation plates are less effective at maintaining distinct thermal zones due to the airflow through the perforations.
Enhancing Safety and Compliance
- Segregation of Hazardous and Non-Hazardous Areas: Safety standards such as IEC 60204 require the segregation of hazardous voltages from user-accessible areas. Separation plates help achieve this segregation.
- Acting as Fire Barriers: In case of thermal runaway or component failure, separation plates can act as fire barriers, containing and isolating potential fire sources within an enclosure.
- Containment of Plasma Fumes: During electrical faults or high-current interruptions, components like Air Circuit Breakers (ACB) and Molded Case Circuit Breakers (MCCB) can generate plasma fumes. These fumes are highly ionized and can conduct electricity, potentially causing short circuits if they spread to other compartments. Separation plates act as physical barriers that contain these fumes within their designated compartments, enhancing safety and reducing the risk of cross-compartment short circuits. However, perforated separation plates are less effective at containing these fumes due to their design.
Ensuring Environmental Protection
- Maintaining Ingress Protection (IP) Ratings: Separation plates contribute to maintaining the enclosure’s IP rating by preventing dust, water, and other contaminants from spreading within the enclosure, thus protecting sensitive electronics.
Enabling Ease of Maintenance
By facilitating easier access and maintenance of individual sections without disrupting the entire system, separation plates help reduce downtime and improve service efficiency.
Types of Separation Plates
Separation plates come in various materials (electro-galvanized, aluminium, mild steel, polycarbonate, etc.), each offering unique benefits and some trade-offs:
- Steel Separation Plates:
Pros:
Durability: Provides excellent mechanical strength and rigidity.
Fire Resistance: Offers high resistance to fire, making it ideal for critical applications.
Cons:
Weight: Steel plates can be heavy, making installation and handling more challenging.
Cost: Generally more expensive compared to some other materials.
Eddy Currents: Susceptible to eddy currents, which can cause unwanted heating and energy loss, especially in high-frequency applications.
- Polycarbonate Separation Plates:
Pros:
Lightweight: Easier to handle and install.
Transparency: Allows visibility of components for inspection without removal.
Cons:
Less Durable: Not as strong as steel and can be less resistant to impacts.
Lower Fire Resistance: Polycarbonate has a lower fire resistance compared to steel.
- Perforated Separation Plates :
Pros:
Ventilation: Allows airflow while maintaining structural integrity.
Cooling Efficiency: Enhances cooling by promoting better air circulation.
Weight Reduction: Perforated polycarbonate plates are lighter, combining the benefits of weight reduction and ventilation.
Visibility: Perforated polycarbonate plates allow visibility of components for inspection without removal.
Cons:
Strength: Perforated polycarbonate is not as strong as perforated steel, which can limit its use in certain applications.
Fire Resistance: Perforated polycarbonate has lower fire resistance compared to steel.
Thermal Zones: Less effective at maintaining distinct thermal zones due to airflow through the perforations.
Containment: Less effective at containing plasma fumes and other byproducts due to perforations.
Eddy Currents: Perforated steel plates are susceptible to eddy currents, similar to solid steel plates.
Conclusion
Separation plates might seem like a small component, but they play a crucial role in the overall functionality of electrical enclosures. By providing electrical isolation, managing EMC, improving thermal management, enhancing safety, offering mechanical and environmental protection, separation plates ensure the reliable and efficient operation of electrical systems. Understanding the different types of separation plates and their pros and cons helps in selecting the right one for specific applications, enhancing the performance and safety of electrical enclosures.
