1. INTRODUCTION Purpose Understand electrical enclosure materials
Objectives
Learn about available electrical enclosure construction materials
Understand the factors used to select the proper enclosure material
Understand the tradeoffs between various materials & their performance impacts
Learning Time
15 minutes
With this presentation, you’ll learn about available electrical enclosure construction materials. You will come to understand the factors used to select the proper enclosure material, as well as understand the tradeoffs between various materials and their performance impacts. 1

2. PROTECT FROM THE ELEMENTS
Industrial automation equipment can be used in almost any environment imaginable. Enclosures must protect these items from harmful elements to extend their life and prevent expensive operations downtime.
Hoffman industrial automation enclosures help protect your customers’ business from the elements.
Industrial automation equipment can be used in almost any environment imaginable. Enclosures must protect these items from harmful elements to extend their life and prevent expensive operations downtime.
Hoffman protects your customers’ vital assets! 2

3. INDUSTRIAL ENCLOSURE MATERIAL TYPES
RATINGS
INDOOR/ OUTDOOR
TYPICAL APPLICATIONS
METALS
MILD STEEL
TYPES 1, 12, 3R, 4
IP20/30/54/55
Indoor
Outdoor non-corrosive
Industrial & commercial applications
304 STAINLESS STEEL
TYPE 4X
IP66/69K
Indoor/Outdoor
Food & Beverage
316L STAINLESS STEEL
Oil & gas, especially offshore oil platforms
ALUMINUM
IP66
Outdoor
Telecommunications
NON-METALLICS
POLY-CARBONATE
Electronics & instrumentation
ABS
NEMA 4X (NON-UL) IP66
Electronics & instrumentation
POLYESTER
Water treatment facilities
FIBERGLASS
Oil & gas
Industrial enclosure material types can be classified as being either metal or non-metallic with several options for each. For metallic enclosures, mild steel is most common and is typically powder paint finished for corrosion protection. For even greater corrosion resistance, 304 (three-oh-four) alloy stainless steel enclosures are typically used, and for the harshest corrosive environments 316L (three-one-six-el). Another corrosion resistant, yet light weight option for metallic enclosures is aluminum.
Non-metallic enclosure material options can be classified as either thermoplastics or fiber-filled composites. Thermoplastic materials include polycarbonate, ABS (A-B-S), and polyester.
For electrical enclosures, fiberglass, also sometimes known as GRP or FRP, is the only readily available fiber-filled composite material.
Different materials affect enclosure performance 3

4. FACTORS IN DETERMINING ENCLOSURE MATERIALS
Environmental considerations
Chemical resistance
Heat absorption & dissipation
Flexibility & ability to modify
Impact resistance & material strength
Weight considerations
Aesthetics
Purchase price
When selecting an electrical enclosure material, many factors must be considered. These include environmental considerations, such as Type or IP rating required, chemicals present, likelihood of damage due to impact, and heat absorption from the surroundings. Other factors to consider that affect an enclosure’s ease of use and installation, are the ability to modify the enclosure and weight. Some customers or users will also care about aesthetics and the appearance of the enclosure. Finally, consider the relative purchase price of different enclosure materials to best meet the customers needs.
Many factors to consider 4

5. ENVIRONMENTAL CONSIDERATIONS
TYPE 1
TYPE 12
TYPE 3R
TYPE 4
TYPE 4X
MILD STEEL
MILD STEEL MODULAR
STAINLESS STEEL
ALUMINUM
NON-METALLIC
The NEMA, UL, CSA, or IEC environmental ratings are a critical factor in selecting the proper enclosure material for an application. This chart shows typical enclosure materials used for the various Type and IP ratings.
For lighter use, indoor environments; such as those that fall into NEMA Type 1, Type 12 and up to IP55 ratings; mild steel or modular enclosures are most common.
For medium, outdoor environments; NEMA Types 3R and 4, and up to IP66 ratings; mild steel and non-metallic enclosures are the choice.
And for heavy, contamination-prone applications, indoor or outdoor; including NEMA Type 4X, IP66 and IP69K ratings; stainless steel, aluminum, and non-metallic enclosures ensure protection from those elements.
IP20/IP30
IP54/55
IP66
IP69K
Environmental ratings a primary factor in material selection 5

6. Hoffman has tested these materials extensively
CHEMICAL RESISTANCE
SOLVENTS
ALKALIS
ACIDS
RECOMMENDED
304 STAINLESS STEEL
316 STAINLESS STEEL
FIBERGLASS
ALUMINUM
POLYESTER
ABS
POLYCARBONATE
SATISFACTORY
MILD STEEL (PAINTED)
LIMITED USE
Another environmental consideration is an enclosures ability to survive in areas containing solvents, alkalis, or acids. These substances can cause corrosion of most industrial enclosure materials. Hoffman has completed extensive materials comparison testing to establish the relative material acceptability chart summarized here. This chart is intended as a general reference guide. It is recommended that if you are specifying or installing an enclosure in an environment where these types of chemicals will be encountered, please refer to the detailed Chemical Resistance Charts in the Hoffman catalog and on hoffmanonline.com.
Click here to access the Chemical Resistance chart
Hoffman has tested these materials extensively 6

7. HEAT ABSORPTION & DISSIPATION
GOOD (LOW)
POOR (HIGH)
HEAT ABSORPTION FROM ENVIRONMENT
NON-METALLICS
MILD STEEL
STAINLESS STEEL
ALUMINUM
GOOD (HIGH)
POOR (LOW)
HEAT DISSIPATION FROM ENCLOSED EQUIPMENT
Specifiers must evaluate both the temperature of the environment in which the enclosure will be located as well as the expected temperature of its enclosed electrical components. These qualities are known as heat absorption and heat dissipation, respectively. Non-metallics are superior insulators and thus have low heat absorption, while metals, and especially aluminum, have a high heat absorption from the surroundings. The same insulating and conducting properties yield the opposite effect when heat dissipation becomes the primary concern. Metallic enclosures, and particularly aluminum, dissipate heat better than non-metallic enclosures. In both cases, where passive, conductive cooling through the enclosure material is not enough to prevent harmful temperature levels, louvers in the enclosure body, solar shields, or even active cooling, such as fans and air conditioners can be used. Hoffman has all of these options available for most enclosure models.
ALUMINUM
MILD STEEL
STAINLESS STEEL
NON-METALLICS
Louvers, solar shields or active cooling equipment can be added 7

8. SIZING FLEXIBILITY & ABILITY TO MODIFY
EASY
DIFFICULT
SIZE ADJUSTMENTS
MILD STEEL
STAINLESS STEEL
FIBERGLASS
POLYCARBONATE
ABS
EASY
DIFFICULT
ABILITY TO MODIFY (HOLES & CUTOUTS)
To accommodate some electrical equipment and connections, many industrial automation enclosures need to be modified with holes, cutouts, or adjusted in size to fit the application. Traditionally much of this has been done in the field; during integration or just prior to installation. Some enclosure materials are highly suited to these modifications while others are not. Mild steel enclosures are relatively easy to add holes and cutouts, and provide easy size adjustments because they are fabricated from sheet metal. Stainless steel enclosures also provide easy size adjustments, but due to material hardness, are more difficult to cut and modify onsite. Non-metallic materials, including polycarbonate, ABS, polyester, and fiberglass are highly suitable for jobsite modifications such as holes and cutouts, but are limited in size flexibility, as they are molded and have specific tooling limitations
Regardless of material, Hoffman has the ability to provide custom size adjustments and/or holes and cutouts directly from the factory, giving you another option to provide flexibility without the challenges of modifying enclosures during integration or at the installation site!
POLYCARBONATE
ABS
MILD STEEL
FIBERGLASS
STAINLESS STEEL
Hoffman can provide modified features from the factory 8

9. IMPACT RESISTANCE & MATERIAL STRENGTH
HIGH
LOW
IMPACT RESISTANCE
POLYESTER
POLYCARBONATE
ABS
STAINLESS STEEL
ALUMINUM
FIBERGLASS
MILD STEEL
HIGH
LOW
MATERIAL STRENGTH
In selecting enclosure materials, a trade-off between resistance to damage and strength to support numerous heavy electrical components must be made.
A measure of an enclosure’s resistance to damage is the impact resistance of its construction material. Non-metallic materials, especially polyester and polycarbonate, have high impact resistance. Therefore, enclosures constructed of these materials are less prone to breakage or deformation when hit by other objects.
Conversely, those same impact resistant qualities require sacrificing some material strength. Material strength should be a consideration when the enclosure is needed to support or contain numerous heavy electrical components. Enclosures constructed from high-strength materials, such as stainless and mild steels, will support a much higher quantity and total weight of devices, but at the expense of impact and damage resistance.
STAINLESS STEEL
ALUMINUM
ABS
POLYESTER
POLYCARBONATE
MILD STEEL
FIBERGLASS
Resistance to damage vs. strength to support components

10. WEIGHT CONSIDERATIONS
RELATIVE WEIGHT FOR GIVEN SIZE ENCLOSURE (EMPTY)
Depending on the application at hand, a lightweight enclosure may be preferable. The relative enclosure weights of a given size for various materials is shown here. Lightweight materials such as aluminum or non-metallic plastic are easier to lift and work with, especially when enclosed components are of significant weight or when the enclosure will be wall or pole-mounted.
Must take into account weight of enclosed equipment 10

11. Hoffman can provide almost any color imaginable
AESTHETICS
Although aesthetics can be very subjective, two enclosures for use in an identical application and environment, can have very different appearances. For example, these two enclosures are of a similar size and ratings, but have significantly different aesthetic characteristics, such as a flush door with quarter turn latches as compared to an offset door with multiple clamps. To match the preferred enclosure aesthetics to the customer, images of Hoffman products can be found on hoffmanonline.com. You should work with your customer to understand their particular needs or preferences.
An increasing number of industrial automation enclosures are required to be branded with company colors, or fabricated to blend in with their environments. Metallic enclosures offer the most capability to tailor to specific aesthetic requirements, through painting one of a myriad array of colors and or patterns, many of which are readily available from Hoffman. Non-metallic enclosures are a bit more difficult, as generally the color is a factor of the molded base material. Non-metallic enclosure colors or looks are much more limited.
Hoffman can provide almost any color imaginable 11

12. AVERAGE PURCHASE PRICE Price needs to align with customer requirements
HIGHEST
LOWEST
AVERAGE PURCHASE PRICE
316 STAINLESS
ALUMINUM
MILD STEEL
POLYESTER
POLYCARBONATE
ABS
304 STAINLESS
FIBERGLASS
Several enclosure materials are available at different price points, helping project managers stay within their budget, while providing the necessary protection required. This chart is meant to be a reference indicating relative cost between materials for a similar sized enclosure. Stainless steels and aluminums are generally the most expensive, reflecting their superior corrosion resistance properties and long expected life. Mild steel is the most common material for indoor industrial applications and carries a moderate price tag. Non-metallic materials tend to be lower priced, but sacrifice longevity. The key is finding the appropriate trade-off between price and benefits.
Price needs to align with customer requirements 12

13. INDUSTRIAL ENCLOSURE MATERIAL TYPES
RATINGS
INDOOR/ OUTDOOR
TYPICAL APPLICATIONS
METALS
MILD STEEL
TYPES 1, 12, 3R, 4
IP20/30/54/55
Indoor
Outdoor non-corrosive
Industrial & commercial applications
304 STAINLESS STEEL
TYPE 4X
IP66/69K
Indoor/Outdoor
Food & Beverage
316L STAINLESS STEEL
Oil & gas, especially offshore oil platforms
ALUMINUM
IP66
Outdoor
Telecommunications
NON-METALLICS
POLY-CARBONATE
Electronics & instrumentation
ABS
NEMA 4X (NON-UL) IP66
Electronics & instrumentation
POLYESTER
Water treatment facilities
FIBERGLASS
Oil & gas
Let’s summarize the most common materials used for industrial electrical enclosures:
Mild Steel is most often used indoors in industrial and commercial applications but can also be used outdoors in non-corrosive applications. Sometimes mild steel is protected with a galvanized coating and painted to increase the corrosion protection characteristics when used outdoors.
304 Stainless Steel is used both indoor and outdoor in corrosive environments and is the preferred enclosure material in the food and beverage industry.
316L Stainless Steel can also be used indoors and outdoors however, is most commonly used outdoors in highly corrosive environments. 316L performs best in high salt environments such as coastal areas and offshore oil platforms
Aluminum is used primarily outdoors and is the preferred enclosure material for the telecommunications industry. Because of its light weight, aluminum is also used when the enclosure is pole-mounted for lighting and security applications.
Polycarbonate is a thermoplastic material suitable for both indoor or outdoor applications. The IP66 and Type 4X rating make it a good choice for wet applications and its non-metallic properties offer good protection in electronic and instrumentation applications. Polycarbonate material offers superior flame retardant properties when compared to ABS.
ABS is also a thermoplastic material suitable for both indoor and outdoor environments. Slightly lower priced than polycarbonate, ABS is also a good choice for electronic and instrumentation applications.
Polyester is a highly durable thermoplastic well suited for outdoor enclosure applications. Its superior performance in ultraviolet environments make it a great material for applications where the enclosure must be mounted in direct sunlight.
Fiberglass, or glass reinforced polyester, is a very rugged thermoset material commonly used outdoors in a variety of applications. Fiberglass enclosures are often found in Oil and gas applications and where solvents are present.
It is vitally important to understand where and how the enclosure is going to be used in order to select the right material to ensure superior performance. The broad selection of enclosure materials available from Hoffman, provides the opportunity to optimize your customer’s solution.
Different materials affect enclosure performance 13

14. Selecting the right material is key to meeting customer needs
SUMMARY
THINGS AN APPLICATION SAVVY ENGINEER NEEDS TO KNOW
Different industrial automation enclosure materials
Different factors to help determine the enclosure material
Which performance characteristics are important to the customer
How different enclosure materials compare in different measures
By following along with this presentation, you’ve learned the different industrial automation enclosure construction materials, what factors are helpful in determining the proper enclosure material, and how the common materials stack up against each other. Armed with this new knowledge and an understanding of for which performance characteristics your customer values, you are equipped to select the right enclosure for your customer.
Selecting the right material is key to meeting customer needs 14