Electronics Protection Online - A Complete Guide to Enclosures and Protection

Electronics Protection

Save Installation Time and Costs by Specifying an Enclosure Complete with Accessories and Thermal Components
Nathan Espinosa & James Swanson, Hoffman Product Managers
Pentair Technical Products

Ensuring reliable performance and long life from electronics is accomplished by protecting them from their environment. In the past, this has been accomplished by ordering the appropriately sized gray box, installing the equipment and hoping the enclosure will withstand its surroundings. Today, customers have more options, including a variety of enclosure types, materials and ratings.

A comprehensive assortment of accessories, hardware and thermal components are also available to complement an enclosure and provide added features, convenience and security. The broad range of locks and latch kits, panels, doors and mounting accessories, keyboards, lighting kits and more can be selected by considering the following factors at the time of purchase: enclosure population, accessibility, environment and mounting.

Populating an Enclosure
By determining what components will populate the enclosure, customers can specify accessories at the time of order, which will help create efficiencies during installation. For example, many customers assume that enclosures come with panels, but they often do not. By ordering panels along with an enclosure, customers can select from various sizes, as well as options such as perforation. This ensures that the enclosures can be easily populated and accommodate the desired components. Some customers may even choose to order the panels ahead of the enclosure so they can populate the panels with electrical components and quickly install the panel when the enclosure arrives.

The method of distributing power may also affect the accessories and hardware required for populating an enclosure. For instance, busbar systems, a predominant power distribution method outside of North America, safely distribute power throughout a panel while conserving valuable panel space. A busbar system uses three copper bars, which are attached to end supports connected to the back panel, to distribute power throughout the enclosure. With a 60 mm busbar system, users can reduce panel size by 25 percent compared with traditional wiring. Knowing the power distribution method prior to specifying an enclosure allows customers to consider how it will impact the size of the panel, and some manufacturers will even provide a drawing of a layout option.

Accessibility Requirements
Doors, locks, lockouts, latches, handles and clamps are some of the accessories available to provide and deny access to components inside an enclosure. While these accessories can be retrofitted, knowing ahead of time the frequency and number of people who will access the enclosure allows customers to define which access options will accommodate their requirements and setup.

The accessibility options should address enclosure security requirements. Depending on the classification, customers can select a key-lock with just one key, slotted locks that multiple users could access with the use of a screwdriver or a padlock. Safety is also a consideration. Electrical interlocks prevent personnel from opening an enclosure door when it is energized. Interlocks can also be programmed to shut processes down when a door is opened.

Levels of accessibility can also be added without the need to open an enclosure door. Window kits allow visual access to the inside of an enclosure. If customers know they require a window when placing an enclosure order, the manufacturer can modify it with the necessary holes. While customers can punch holes and perform most other modifications in-house, it is often more convenient to order pre-punched enclosures with holes to meet an application’s requirements. This reduces installation time and prevents the customer from dealing with modifying the enclosure.

Additional data access and control can be achieved through the use of folding shelves and data interface ports. Folding shelves are positioned on either the inside or outside of the enclosure the door. If placed outside of an enclosure the shelves can support a laptop, which may be set up to monitor electronics within an enclosure, providing easily accessible data to operators. Data interface ports are a solution for the intersection of convenience and safety. Ports are mounted on an enclosure to allow access to the programming devices inside the enclosure without opening the enclosure door. An important accessory for use with a broad range of enclosures, these ports maintain compliance with the NFPA 70E arc flash protection directive.

Environment/Thermal Considerations
New electronic components pack more power into smaller packages, creating a threat to system integrity. Additional power usage results in more heat being generated. This heat must be eliminated to protect the components from overheating and ensure performance efficiency. Fans, blowers, louvers, vents, air conditioners and heat exchangers are some of the solutions employed for thermal management. To determine the best thermal management products, customers need to define information about the environment, enclosure and the equipment inside.

Cooling configurations are classified by several categories. Open loop cooling utilizes the ambient or outside air, filtered or unfiltered, to cool the electronics. Open loop solutions include fans, which cannot provide cooling beyond the ambient air temperature. Closed loop systems, including air conditioners and heat exchangers, maintain the sealed integrity of the enclosure, while utilizing the internal cabinet air to cool the electronics. These thermal management tools are employed as part of either active or passive systems. Active cooling relies on an external device to enhance the cooling process, while passive cooling occurs via natural convection and heat dissipation.

Environmental accessories include corrosion inhibitors, drip shields and moisture removal accessories. Corrosion inhibitors can be snapped into an enclosure at any time, and drip shields can be used in washdown environments to direct moisture away from an enclosure. Drains, vents and dehumidifiers are used to remove and eliminate moisture, which can cause damage to electronics.

Considering the appropriate thermal management and environmental accessories prior to purchasing an enclosure allows customers to plan layouts that guarantee sufficient space for all accessories with no clearance issues. Additionally, accessories are usually rated for a certain environment. Pre-ordering the appropriate thermal management and environmental accessories can have the added benefit of the manufacturer installing accessories to ensure compliance testing, as well as maintain ratings.

Mounting Accessories
Customers should also determine how an enclosure will be mounted and order the appropriate accessories. Options include DIN rail or panel mounting, wall-mount styles, floor-stand enclosures and more. Accessories support these mounting options, as well as other enclosure requirements.

A pole mounting kit can be ordered to allow wall-mount enclosures to be positioned on a pole while floor stand kits allow room for cable entry underneath a cabinet, as well as positioning of a vent drain. Enclosures can be mounted via pendant arm or pedestal, and suspension systems allow customers to suspend an enclosure at a given length, supporting ergonomic positioning of the enclosure for various users. Casters allow mobility for applications such as test equipment, where the enclosure must be carted from one spot to another. Easy-to-clean mounting kits are also available for sanitary environments.

As with the previous considerations, determining the type of mounting when ordering an enclosure allows enclosure manufacturers to make necessary holes and other accommodations. By factoring in the accessories, hardware and thermal management solutions required by a specific application, customers can order an enclosure with the functionality needed to ensure reliable performance, save on installation time and costs, and support future growth throughout the enclosure’s long life.

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