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| NEMA Type | Definition |
| 1 | General-purpose NEMA 1 enclosures protect against dust, light, and indirect splashing, but are not dust-tight. They primarily prevent contact with live components and are typically used indoors under normal atmospheric conditions. |
| 2 | NEMA 2 enclosures are drip-tight general purpose enclosures with the addition of drip shields, primarily used in severe condensation applications. |
| 3 | The weather-resistant NEMA 3 enclosures protect against falling dirt, windblown dust, and weather hazards such as rain, sleet, and snow. It can also withstand the formation of ice. It is typically used outdoors for ship docks, construction work, tunnels, and subways. |
| 3R | NEMA 3 enclosures that omit windblown dust protection. |
| 3S | NEMA 3 enclosures that are optimized to operate when laden with ice. |
| 3X, 3RX, 3SX | The NEMA 3X subclassification indicates additional corrosion protection and are typically used for applications near salt water. |
| 4 and 4X | These watertight NEMA 4 enclosures must exclude at least 65 GPM of water from a 1-in. nozzle when delivered from a distance not less than 10 ft for 5 min. They are typically used outdoors on ship docks, in dairies, and breweries. NEMA 4X enclosures provide additional corrosion resistance. |
| 5 | NEMA 5 dust-tight enclosures provide additional gaskets or equivalent to exclude dust and are typically used in steel mills and cement plants. |
| 6 and 6P | These submersible NEMA 6 enclosures feature designs that meet specified conditions for pressure and time. They are submersible in water or oil and typically used in quarries, mines, and manholes. The NEMA 6 specification is for temporarily submersible enclosures, while the 6P classification can withstands occasional prolonged submersion. Neither are intended for continuous submersion. |
| 7 | NEMA 7 enclosures are certified and labeled for use in areas with specific hazardous conditions. They are specified for indoor use in Class I, Groups A, B, C, and D environments as defined in NFPA standards such as the NEC. |
| 8 | NEMA 8 enclosures are certified and labeled for use in areas with specific hazardous conditions for either indoor or outdoor locations classified as Class I, Groups A, B, C, and D as defined in NFPA standards such as the NEC. |
| 9 | NEMA 9 enclosures are certified and labeled for use in areas with specific hazardous conditions for either indoor or outdoor locations classified as Class II, Groups E, F, or G as defined in NFPA standards such as the NEC. |
| 10 | NEMA 10 enclosures meet the requirements of the Mine Safety and Health Administration (MSHA), 30 CFR Part 18 (1978). |
| 11 | NEMA 11 general-purpose enclosures protect against the corrosive effects of liquids and gases. They meet drip and corrosion-resistance tests. |
| 12 and 12K | NEMA 12 general-purpose enclosures are intended for indoor use and provide a degree of protection against dust, falling dirt, and dripping noncorrosive liquids. They meet drip, dust, and rust resistance tests. |
UL508A is the UL standard for the construction of Industrial Control Panels. OSCO uses UL requirements to properly select components, wiring methods, and enclosures. Upon customer request, OSCO will follow 508A; the UL standard for safety for industrial control panels and apply the UL cULus label.
NEMA is the National Electrical Manufacturers Association. They provide the enclosure ratings system for industrial control panels.
The National Electrical Code (NEC) was developed by the National Fire Protection Association (NFPA) to define safety standards for electrical equipment and installation methods. They are commonly used by states, municipalities, and cities with the authority to approve electrical installations that meet NEC standards.
The International Society of Automation (ISA) develops global standards for process automation and certifies industry professionals.
The National Fire Protection Association (NFPA) has defined a classification system for hazardous locations as part of the NEC. This system delineates Classes, Divisions, Zones and Groups that can be combined to define the hazardous condition of a specific area.
Occupational Safety and Health Administration (OSHA) has adopted this classification system from the NEC and they are redefined in 29 Code of Federal Register (CFR) 1910.399.
Class defines the type of flammable substance present.
- Class 1 indicates the presence of flammable gas or vapors.
- Class 2 indicates the presence of combustible dust.
- Class 3 indicates the presence of ignitable fibers or flyings
Division indicates the degree of exposure to the explosive substances.
- Division 1 indicates constant exposure to these ignitable substances.
- Division 2 Indicates that the area is only exposed to combustible substances in the event of a leak.
Zone defines the likelihood of ignitable concentrations for an area.
Group defines the actual type of combustible material.
PLCs (Programmable Logic Controller) or PACs (Programmable Automation Controllers) are dedicated computers that are programmed to automate electromechanical processes. They are custom-programmed for each application and can be configured to support multiple input and output arrangements. PLCs are designed to operate in extreme temperatures and can withstand vibration and electrical noise.
Variable Frequency Drives (VFD) are adjustable speed drives that are used to control AC motor speeds and torque by modifying motor input voltage and frequency. OSCO routinely incorporates VFD controls into control systems.
OSCO will partner with OEMs to provide UL listed control systems that are safe, easy-to-use, and consistently scalable across a range of equipment as required.
- Single-Phase power is a two wire alternating current (AC) circuit with one power conductor and one neutral conductor.
- Dual-Phase power provides two 120V single power circuits that can also be combined into a single 240V dual-phase power circuit. It consists of two power conductors (120V, 120V) that are out of phase with each other and one neutral conductor. This is the standard household power arrangement in the USA.
- Three-Phase power is a three wire AC power circuit with three power conductors that are out of phase with one another and one neutral conductor. It can be arranged to provide three 120V single phase circuits or configured as one 208V three-phase circuit. There is also a three-phase power that is 460 volts.
