Every Manufacturing Process Depends on Utility Cabinets
Utility cabinets are the furniture of industry. They can be found as small push-button boxes all the way up to room-sized control cabinets for machinery or process controls. Every manufacturing process depends on at least one cabinet (and often several) to house the control components, switches, relays, fuses, and breakers that make the process operate.
NEMA Standards for Utility Cabinets
NEMA standards determine the environment in which the utility cabinets may be used. The standards specify indoor/outdoor use, resistance to water, dust or other air-borne contaminants and several other specifications. The NEMA ratings types are: type 1, type 3R, type 3S, type 4, type 4X, type 6P, type 12 and type 13. Each of these types is defined in the NEMA standards literature. In practice, many utility cabinets will be type 4&12 which combines the two standards into an enclosure suitable for indoor use with some exposure to dripping water or oil.
NEMA type 1 enclosures are suited for motor start/stop controls where sealing out water or dust is not required. They may have latching doors but no gasketed seals. Type 3R enclosures are used in outdoor situations where the box is exposed to falling rain, and sleet or indoors where dripping water is a problem. Type 3S boxes add additional resistance to problems caused by ice formation. Most machine tools use type 4 cabinets because this type is more resistant to pressurized water or machine tool cutter coolant. These have gasketed and clamped doors. NEMA 4X cabinets are made of corrosive resistant materials such as plastic or stainless steel and are used where the worst environments are encountered. Expect to see 4X cabinets use in food processing where regular wash-down with strong cleansers is part of the environment. Type 6P boxes are water proof for limited depth submersion and are rarely used for industrial applications. Type 12 cabinets are commonly used indoors for automated controls and electronic drives. They are sealed against dust, water and oil.
Specific Utility Cabinets
When specifying utility cabinets for an application there are several things to consider. The environmental conditions to be encountered will determine which NEMA type should be used. The size must allow for all components that will be mounted to the sub panel as well as to the door. There is also heat generated by the components that must be dissipated. An oversize box may be required due to heat concerns. Do not forget accessories like latches, lighting kits and cooling systems. In most cases the supplier will be glad to help the engineer make the proper choices.
Almost all utility cabinet manufacturers offer custom design services and will build a cabinet to customer specifications. Operator consoles are one form of utility cabinet that can be custom manufactured to meet almost any need. A wide variety of materials is available. Cabinets are made of painted/powder coated steel, galvanized steel, stainless steel, aluminum, plastic and glass-reinforced polyester. Some suppliers also offer pre-assembled control cabinets and panels with pre-punched holes for switches and other components. The range of utility cabinet designs and construction is virtually unlimited.
