IQS Newsroom Articles on Electronic Enclosures
About Electronic Enclosures and Electronic Enclosure
Manufacturers Including: Computer
Enclosures, Metal
Box, Metal
Enclosures, NEMA
Enclosures & Plastic
Enclosures.
Electronic enclosures house a wide range of electronic
equipment. They are a standard component in most industrial settings.
These enclosures protect electrical and electronic components from moisture,
chemicals and dust, which can damage the equipment permanently. Electronic
enclosures are typically box-shaped and often have removable panels or
doors to provide the easy access needed for maintenance and equipment
modifications. The temperature and humidity within an electronic enclosure
may also be controlled. Electronic enclosure manufacturers can produce
electric enclosures as small as a pushbutton enclosure, which simply
protects the surrounding area and wiring of a electrical push button,
or as large as a room in which is housed large, sensitive computer networks
and wiring. Wiring itself often needs to be enclosed in a protective
enclosure, especially at the connection points of two or more types of
wire or from the wire to the main equipment. These types of enclosures
are called junction or terminal boxes.
The housing material used by electronic enclosure manufacturers is generally
made from sheet
metal, such as stainless steel or aluminum. However, other materials,
such as fiberglass, high strength polymer plastics and other composites
are also used, especially for portable devices. These materials are
lighter weight and more durable than steel. Materials should be chosen
for the desired properties of electrical, thermal and fire resistance
and strength. Electronic enclosures can be coated with a substance that
protects the internal equipment from EMI, which stands for "electromagnetic
interference." This type of extra protection is necessary for
sensitive electronic equipment in which EMI would disrupt efficient
performance of the circuitry inside the equipment.
Electronic enclosures are made available by electronic enclosure manufacturers
for portable devices, as well. There are two basic sizes of portable
devices: pocket and handheld. Pocket boxes measure no more than two
or three inches and typically house a single board and components. Pocket
enclosures offer several different types of accessories, including body
clips, keypads, key rings and buttons. Handheld enclosures measure between
six and 11 inches and house larger components than pocket enclosures
and multiple boards. Handheld boxes offer a wide variety of accessories
and can easily accommodate cable glands, display areas, separate battery
compartments and recesses for membrane keypads or product labels. Both
handheld and pocket enclosures are usually made of ABS (acrylonitrile-butadiene-styrene)
plastic.
Customized enclosures are commonplace in many industries, such as the
medical, automotive and agricultural industries. Electronic enclosures
should be an integral part of the design and should be considered early
in the process, rather than near the end, to prevent problems or critical
failures. Factors to consider when selecting an appropriate enclosure
include size, NEMA type, materials of construction, mounting and security.
The enclosure size is determined by the dimensions of the equipment
that the electronic enclosure will house, as well as other factors,
such as service connections, equipment mounting, internal and external
access, thermal limitations, maintenance, economics and future expansion.
The NEMA type selected depends on the environment of the application.
Materials for enclosures should meet corrosion and strength requirements.
Mounting methods for electronic enclosures include floor standing and
pole-, wall- and pedestal-mounting. Padlock hasps, locking latches,
key locks, fiberglass latches, wing-knobs and screw covers provide security
for the enclosure.
Types of Electronic Enclosures
-
are housings made specifically for computers. Computer enclosures are
usually made of metal and are used to protect the inner electronics
from dust and moisture damage.
-
are made to the detailed specifications of the customer. The sizes
can vary to enclose a range of equipment, from a fuse box to a number
of electronic devices and cables housed in a separate room, referred
to as network racks.
-
have an inner wall that is isolated from the outer wall with the exception
of the region where the power-line filters and coaxial connectors
penetrate. Double shielded enclosures can also be rooms.
-
are filters designed to protect electronic parts from damage caused
by dirt, oil, dust and moisture. Electronic cabinets, used in virtually
every industry, give electronic components a plane of operation that
improves their efficiency.
-
involves using materials, such as filters, gaskets and coatings to block,
absorb or redirect electromagnetic waves, in order to prevent electromagnetic
interference (EMI) from harming sensitive equipment. These materials
are attached to the metal surface of such enclosures.
-
are a type of enclosure used specifically for wiring and the connecting
of wiring to a larger unit and are often constructed with metal material.
Junction boxes must have a cover plate and should be easily accessible.
- are metal enclosures that protect electronics.
-
are typically made of either aluminum or sheet metal. Metal enclosures
are being replaced by enclosures made of lighter, more durable composites.
-
are a specific type of electronic enclosure that is certified by the
National Electronic Manufacturers Association (NEMA), which rates the
enclosures bases on the type of application for which they are used.
NEMA enclosures are typically made from carbon or stainless steel and
can range in size from a pushbutton panel to a room-sized panel.
- are plastic housings that protect electronics.
-
are either rectangular or wedge-shaped. Pushbutton enclosures have cutouts
for surrounding and securing pushbuttons and can be mounted to a wall,
pedestal or suspension system.
-
are similar to junction boxes and are used for the housing and protection
of a connection point between two different types of wire.
Electronic Enclosures Terms
-
A reduction in signal strength. Attenuation can occur naturally during
normal signal transmission, or it may be produced intentionally by inserting
a device in the path of the signal to reduce signal strength.
- The outer
surface of the electrical enclosure.
- Often used interchangeably
with either enclosure or rack. It is a piece of equipment designed to
house or enclose something, such as electrical or process equipment.
- Seals that prevent
water, dust, etc. from entering the enclosure at the point at which the
cable is brought through the enclosure wall. Often, cable glands are installed
via a gland plate.
- The unintentional or undesired exiting of potentially interfering
electromagnetic energy from electrical/electronic sources.
- The ability
of a material to resist burning, sparking, sputtering or dripping when
brought into contact with a naked flame. Not all enclosures are flame
retardant.
- Also called a "mounting
plate" or "mounting pan," it is a shelf that allows
the mounting of equipment inside the enclosure. Gear trays are typically
located at the rear of the enclosure, though some may be movable.
- Removable section
of the enclosure, usually located on the bottom. The gland plate can be
removed to allow the easy fitting of cable glands.
- The extent to
which a material can be magnetized.
- Term used to describe
various styles of mounting bases for floor-mounted enclosures.
- Cables that
have shields, such as braids or foils, to prevent EMI from entering
or exiting the cable.
- The input current
of the equipment as declared by the manufacturer.
- Vents that
are used for HVAC or simple ventilation of shielded products, such as
cabinets, rooms or enclosures. Some shielding vents also provide high
shielding or air filtering.
- Shielding
consisting of a thin conductive film on the glass or a fine-wire mesh
or metalized open-mesh textile.
- A material
that maintains shielding effectiveness across a seam or gap in an electronic
enclosure.
- A NEMA rating indicating
that the enclosures are intended for indoor, non-hazardous locations.
Type 1 enclosures are mainly used to provide protection against limited
amounts of falling dirt.
- A NEMA rating indicating
that the enclosures are intended for use in outdoor, non-hazardous locations.
Type 3R enclosures are mainly used to provide protection against falling
rain and external ice formation.
- A NEMA rating indicating
that the enclosures are intended for indoor or outdoor use in non-hazardous
locations. Type 4 enclosures are mainly used to provide protection against
splashing or hose-directed water, damage from external ice formation and
windblown dust or rain.
- A NEMA rating indicating
that the enclosures are intended for indoor use in non-hazardous locations.
Type 12 enclosures are mainly used to provide protection against dripping,
non-corrosive liquids, circulating dust and falling dirt.