Honeywell Apex - APPENDIX D - Glossary; Glossary of Technical Terms

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MAN0604_Issue 09_02-2013 Apex
2110M8030
APPENDIX D - GLOSSARY
Cartridge
A replaceable assembly containing a gas transducer and associated calibration information.
Catalytic Bead
Used for the detection of combustible gases. These are made of an electrically heated platinum wire
coil,coveredrstwithaceramicbaseandthenwithanaloutercoatingofcatalyst.
CE mark
Indicates compliance to all relevant European directives.
Electrochemical Sensor
A gas sensitive electrode, formed by a permeable membrane and special electrolyte.
Gas Transducer
An element that translates gas concentration into an electrically measurable quantity, such as
electrochemicalcells,catalyticbeadsandthicklmdevices.
LCD
Liquid Crystal Display.
LEL
Lower Explosive Limit is the lowest concentration of fuel in air which will burn and for most
ammablegasesandvapoursitislessthan5%byvolume.
Note:forsomegases(e.g.methane)theLELlevelhasdifferentvaluesintheEuropeanandNorth
American standards.
LEL%
PercentageoftheLowerExplosiveLimit(forexample,10%LELofmethaneisapproximately0.5%
by volume).
LON
Local Operating Network.
PCB
Printed circuit board.
Peak
Maximum, or minimum, measurement since switch on.
PPB
Parts per billion concentrations in the atmosphere.
PPM
Parts per million concentrations in the atmosphere.
rh
Relative humidity.