Emerson Rosemount CT5800, Manual

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E Glossary and abbreviations
The following terms are used in this manual.
Term Description
Caution Signal word used to indicate a potentially hazardous situation which, if not
avoided, could result in equipment damage.
Danger Signal word used to indicate an imminently hazardous situation which, if not
avoided, will result in death or serious injury.
Detection limit Although the gas detection range is given from zero, this is the lowest possible
level of gas that the Rosemount CT5800 Gas Analyzer can detect.
Explosive gas(es) Flammable gases and gas mixtures in a mixture with air within the explosive
limits.
Flammable gas(es) Gases and gas mixtures are assigned to be flammable if they might become
ignitable when in a mixture with air.
Infallible containment This term is derived from the standards of explosion protection especially from
the requirements for pressurized housings; thus an infallible containment can
be characterized by no intended leakage into the gas paths enabling gas to
enter the inner compartment of the analyzer housing.
Intrinsically safe cell (IS cell) Cells supplied with an intrinsically safe power signal, approved by a test
institute, to operate with explosive gases. The design ensures the IS cells
remain safe even in case of failure, and explosive gases are not ignited.
Laser beam path length The optical distance traveled by the laser through the gas being measured.
Lower explosion limit (LEL) Volume ratio of flammable gas in air below which an explosive gas atmosphere
will not be formed; the mixture of gas and air lacks sufficient fuel (gas) to burn.
Measurement frequency The frequency at which all gas concentrations are updated.
NAMUR NAMUR is an international user association of automation technology in
process industries. This organization has issued experience reports and working
documents, called recommendations (NE) and worksheets (NA).
NEMA
®
National Electrical Manufacturers Association. 4X specifies a degree of
protection to personnel against incidental contact with the enclosed
equipment, to provide a degree of protection against falling dirt, rain, sleet,
snow, windblown dust, splashing water, and hose-directed water, and that will
be undamaged by the external formation of ice on the enclosure.
Protection Class IP66 Both terms are used to specify conditions for equipment to be installed
outdoors. IP stands for ingress protection; the first number specifies protection
against solid objects (6 = dust tight) while the second number specifies the
degree of protection against liquids (6 = heavy seas).
Purge A purge is the use of high pressure gas to remove particulates that may have
built up on the cell mirror surfaces.
Replace In the repair procedure, replace means to remove and discard an unserviceable
item and then fit a serviceable replacement item.
Sample flow rate The rate at which sample gas flows through the cell
Reference Manual Glossary and abbreviations
00809-0100-5800 September 2019
Rosemount CT5800 183