5017T Flat Panel Industrial Touch Monitor Chapter 2 – Installation
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Note
Electrical equipment cannot be installed in Division 1 locations unless they
are intrinsically safe, installed inside approved explosion-proof enclosures, or
installed inside approved purged and pressurized enclosures.
Division 2 Locations
••••
Class I volatile flammable liquids or flammable gasses are handled, processed,
or used, but confined within closed containers or closed systems from which
they can escape only in cases of accidental rupture or breakdown of such
enclosures or systems, or in case of abnormal operation of equipment.
••••
Ignitable concentrations of Class I vapors or gasses are normally prevented by
positive mechanical ventilation, but which may become hazardous due to
mechanical failure of those ventilation systems.
••••
Location is adjacent to a Division 1 location.
••••
Class II combustible dust is not normally in the air in quantities sufficient to
produce explosive or ignitable mixtures. Dust accumulations are normally
insufficient to interfere with normal operation of electrical equipment or other
apparatus. Combustible dust may be in suspension in the air as a result of the
following: infrequent malfunctioning of handling or processing equipment;
combustible dust accumulations on, or in the vicinity of electrical equipment;
may be ignitable by abnormal operation or failure of electrical equipment.
Groups
All electrical equipment that is approved for use in hazardous locations must include
a group rating. Various flammable and combustible substances are divided into these
groups as a function of their individual maximum experimental safe gap (MESG),
explosion pressure, and ignition temperature.
Component temperatures and the potential for spark based upon voltage, current, and
circuit characteristics, within electrical equipment, will determine what the
equipment group rating will be. A device approved for installation within Class I,
Group A locations may also be used in Groups B, C, or D.
Note
Approved Class I equipment may not be suitable for Class II installations.
Class I includes Groups A, B, C, and D. Class II includes Groups F, and G.
