As product and process technologies change and improve, enclosure
technology must change along with them. For instance, today's enclosures range
from simple storage devices to complex climate-controlled units. So more than
ever, enclosure designs must provide flexible solutions for wide-ranging
environments-and still meet a variety of tough standards.
Take a look at the way engineers are designing with electric drives and you'll see a shift toward more intelligent control systems. Gradually, the control function is becoming more decentralized. Flexible, computer-controlled systems are replacing systems with centralized control. As a result, PCs have become commonplace on the plant floor.
All-in-one PC enclosures. For enclosure makers, this trend creates a new set of packaging concerns. Rittal Corp., Springfield, OH, took this into account in the design of its latest PC enclosure.
The Rittal unit protects a standard office PC, housing both the CPU and monitor. A pull-out drawer for the keyboard features a built-in mouse pad. An internal lock on the front panel secures the drawer. The enclosure also includes a one-piece monitor window made of safety glass to help protect sensitive inside components, but doesn't dilute screen visibility. For added versatility, the enclosure can be used as a desk-top unit or mounted on a mobile pedestal.
And with the move to intelligent control systems and the surge in integrated electronics technology, a new breed of enclosures has evolved. "They are no longer just metal boxes,"says Peter Werwick, industrial products manager at Rittal Corp., "but system integrated solutions."
New technologies are being combined to create systems with completely new packaging considerations. To meet these needs, industrial enclosure designs must focus on three things, says Werwick: Customization, maintainability, and the integration of various technologies while maintaining NEMA integrity.
Use of operator interface computers has increased in process industries, again requiring more specialized enclosure designs. Case in point: The APX(R) stainless-steel, operator interface (OI) enclosure from Hoffman Engineering, Anoka, MN.
The enclosure mounts on a pedestal, making it possible to move the stand-alone OI device almost anywhere. That's why Mark Smith, electrical engineering manager at Shick Tube-veyor, Kansas City, MO, chose the versatile enclosures. About 75% of Shick's business revolves around supplying pneumatic systems and equipment to companies in the food processing and baking industries. "Our customers can place the unit at nearly any location in their plant and not have to worry about a support structure," says Smith.
Another plus for Shick's customers: environmental resistance. The enclosures are rated UL/CSA Type 4X (IP66) and can withstand salt spray, cleaning solvents, and corrosive process byproducts.
An array of options enables the unit to house the latest operator interface work stations. Three different sloped tops fit the enclosure to most OI brands; while a variety of front accessories can accommodate keyboards, mice, and pushbuttons, or provide a convenient writing surface.
Keeping things cool. Electronics, especially in industrial and data communications applications, are being packed more densely into small spaces. This, in turn, has created the need for smaller enclosures. More importantly, reliable enclosure climate control has become a necessity.
Excessive heat-loads can drastically reduce the life span