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Definition of Electronic Enclosure

In EMS (Electronics Manufacturing Service) industry, we usually call the structure which is used to enclose, contain or protect the electrical, electronic or mechanical components as enclosure (sometimes we also use box, case or housing instead).

Enclosure is the skin and protection of an electronic component / equipment / product. It’s typically made from plastic or metal. Electronic enclosures are generally designed to be used in a wide range of industries and environments. They have different ratings according to their working conditions.

For common consumer electronics, when designing or purchasing the enclosures, people mainly take functionality, accessibility, cost and aesthetics into consideration. While for special or high-end electronics, apart from the common concerns, more features and factors need to be considered depending on different environmental conditions which the enclosures will protect against, such as various of extreme environments.

Our Capabilities on Designing and Manufacturing Electronic Enclosures

In X-Parts, we have 8 electrical engineers and 2 mechanical engineers. With their professional expertise and abundant project experience on circuits and mechanical structure design, we are capable of handling most of the cases in house.

If you didn’t have a 3D drawing, we will do the design and manufacture for you upon our thorough communications on functionality (general protection, shielding radio frequency interference or electromagnetic interference etc.), operating environment ( hazardous or not, climate features, indoor or outdoor etc.) and project budget etc.; If you had a 3D drawing ready, we will do design modifications and manufacture as required.

Functionality and quality are significant, but cost is also vital. As a turnkey solution provider for Electronics Manufacturing Service (PCB Design, PCB Fabrication, Components Sourcing, Enclosure Design & Manufacture and Finished Product Assembly), we usually don’t analyze electronic enclosures independently but evaluate them among the whole project, we always do our utmost to get the best balance between quality and price.

Please feel free to share your ideas with us, we will figure out the most suitable solution for your electronic enclosures together.

Electronic Enclosures Design_2 Electronic Enclosures Design_3

Ratings of Electronic Enclosures

As per the National Electrical Manufacturers Association (NEMA), the electronic enclosures have been identified into eight NEMA ratings. i.e., Type 1, 3, 4, 4X, 6, 6P, 7, and 12. Among them, NEMA 1, 3, 4, and 4X are the most commonly used ones. These NEMA ratings define and demonstrate the ability to withstand specific environments and hazards of an electronic enclosure. These ratings are very helpful for engineers to make their choice and decision for enclosures.

Below are some main characters of the commonly applied NEMA ratings for your reference.

Rating 1 enclosures are mainly designed for indoor use, which provide the very basic protection against dust, dirt and accidental contacts with the component / device / equipment.

– Cost-effective
– Usually easier in design and manufacture

– Only be able to provide very basic protection and work under common environments
– Only have very basic ventilation ability

Rating 3 enclosures can work under both indoor and outdoor environments. But they are more utilized outdoors because of their better protection against various climates and weathers under moderate environmental conditions.

– Capable of protecting against falling dirt, rain, hail, snow and external icing etc.
– Suitable for more commercial and industrial applications
– Suitable for more indoor and outdoor conditions

– Still the lower rating for outdoor utilization due to limited durability and stability
– May bring potential safety hazards when used under outdoor environments

PCB Enclosure Design and Manufacturing

Rating 4 enclosures show a much better performance on protecting against moderate to harsh environments than the previous two ratings above. They are also designed for both indoor and outdoor applications. Plus their weatherproof and watertight features, these enclosures are the good choice for outdoor applications which have to work under exposed environments, e.g. outdoor wiring and power systems etc.

– Weatherproof
– Watertight

– Higher Cost
– Usually heavier (mainly made from metal materials)

Rating 4X enclosures cover all the advantages of rating 4 type but with a greater ability of corrosion protection. So they are widely used for harsh and extreme environments (e.g. seriously humid climate, corrosive chemicals and sustaining overheating etc.)

– Weatherproof and watertight
– Corrosion-resistant
– More stable and durable

– More expensive
– More complicated in design and manufacture
– May take a longer lead time

NEMA 6 & 6P
Rating 6 and 6P enclosures are submersible, which can be applied to both indoor and outdoor conditions. They also provide much stronger corrosion protection than 4X does. And 6P is the enhanced version of rating 6.

Electronic enclosures in NEMA 6 & 6P are submersible in water or oil, so they are ideal for working in quarries, underground mines and manholes etc.

– Enhance capabilities for working under harsh environments
– Submersible

– High cost
– More complicated in design and manufacture
– May take a longer lead time

Except these ratings, there are also some other ratings defined by NEMA. For more details about other NEMA ratings for electronic enclosures, please refer to NEMA enclosure types via encyclopedia.

Enclosure Design for Circuit Boards

Materials of Electronic Enclosures

There are different material types that can be selected for your electronics enclosures. The choice of the material will be decided by multiple factors, such as the specific applications, characteristics of performance, personal preference (aesthetics) and project budget etc. Here we list some of the most commonly used material types:

Type 1: Plastic

Due to its typical features such as low cost, miscellaneous functions and ease of manufacturing, plastic is one of the most popular materials for electronic enclosures. Plastic enclosures can be easily shaped through mold injection, and they can be manufactured in various of colors and surface treatments. The most commonly used plastic enclosures include ABS, polycarbonate, and nylon.

Type 2: Metal

Metal enclosures provide much better performance on durability and corrosion-resistant than plastic enclosures do. They also provide excellent shielding function against electromagnetic interference (EMI). Aluminum, steel and zinc are the common types of metal materials for electronic enclosures.

Mold Injection_X-Parts

Type 3: Composite Materials

To achieve a good balance among durability, weight and cost, composite materials which are combined by two or more materials will be considered. e.g. fiberglass, carbon fiber and carbon steel etc.

Type 4: Glass

For some electronic products which pursuit a high-end and aesthetic appearance, glass enclosures might be used. However, glass materials can be very fragile and heavy, they may not provide the ideal protection as other materials do.

Type 5: Ceramics

The same as glass materials, ceramics can be fragile and heavy, but they are heat-resistant that can be applied under extreme temperatures and provide excellent protection against electromagnetic interference.

Mold Injection_1

Electronic Enclosures Design Considerations and Guidelines

A mechanical enclosure adds various values to an electronic board. It can provide protection for the board, or bring aesthetic and business values when you sell the electronic board with enclosures as a commodity.

Furthermore, the enclosures of your electronic products also reflect the brand image and intellectual property of your company. So below we share some tips and guidelines of electronic enclosures design for your reference.

● Create A List of Requirements
● Product Application
● Production Volumes Forecast
● Project Budget
● Product Aesthetics
● Other Important Considerations

Create A List of Requirements

– What components will be put into the enclosure?
– What are their functions?
– How will they interact with the inside and outside environment?

You should have a clear idea for the three questions above. It’s better to generate a Bill of Materials (BOM), which can be used as a checklist to ensure you make proper rooms for all the components needed.

Product Application

Application of the finished electronic products has a very critical impact on their design. Different operating environments and conditions may require totally different enclosures design strategies. For example, you can’t apply the same design rules for indoor and outdoor electronics. Or designing for common consumer electronics shall be completely different from designing industrial or automotive grade products. Therefore, it’s necessary to consider product applications before and during design stage for your electronic enclosures.

Production Volumes Forecast

Production volumes or market potential assessment before your electronic enclosures design is important. For mass production, mold injection can be a good option due to its lower unit cost. For samples or small volumes, cost and lead time are more critical, so 3D printing or sheet metal press bending can be considered.

Project Budget

Tooling cost of new product development is usually very expensive. So it’s vital to consider cost factor from the initial phase of design. After a comprehensive analysis on your product functions, applications and volumes, then choose the suitable solution for electronic enclosures design.

Product Aesthetics
Please don’t ignore the significance of the aesthetics during your design. Aesthetic appearances (i.e. shape, texture, color and dimensions etc.) are key selling points for some electronic products. But we also no need to overemphasize the importance of aesthetics during electronic enclosure design, functionality and cost usually should always take the first place.

3D Modelling for Electronic Enclosures Design-3

Other Important Considerations

Safety is the most important principle that must be embedded in mind when doing mechanical system design. Electronic enclosures designer should ensure that the system can comply with relevant safety regulations and standards.

The electronic enclosures should be designed to allow for convenient maintenance, repair and replacement of components. Designers should take these into consideration at the very first beginning of the design.

3.Clearance & Tolerance
Manufacturers and machines with different technologies and capabilities will have totally different shrinkage, distortion and tolerance values. To avoid the issues, electronic enclosures designer can apply 3D modelling for the mechanical parts and consider a safety clearance which will fit with the machine tolerance.

3D Modelling for Electronic Enclosures Design-6

In summary, please do remember to take these key points into consideration when designing your electronic enclosures:

– Work out your BOM for components.
– How does it contain and organize wires, PCBs and other electronic components?
– How can it be accessed conveniently to its inside when needed?
– Please consider to design fillets, bosses and ribs when necessary.
– Consider clearances for ports and parts.
– Consider ventilation if needed.

We hope this article could be helpful for your electronic enclosures design. Please feel free to check more details about our capabilities on electronics designing and manufacturing.