2000-OSM, F1
G-1
GLOSSARY
A/D converter
device that converts an analog signal to a digital value
analyzer
process
gas
chromatograph
ASCII
American Standard Code for Information Interchange; standardized computer
coding for printed characters
Auto Zero
procedure bringing the detector signal as close to electrical zero as possible;
brings the signal into the most sensitive area of the A/D
baseline
reference point from which peak height or peak area is measured on a
chromatogram; detector signal level at which no components are detected
benchmark
sample known to be a definite concentration; used to compare an
analyzer's present performance to its past performance
calibration run
analysis that involves injecting a standard sample consisting of specific
components whose concentrations and elution sequences are known
CE Mark
certification process and marking which denote that analyzer complies
with applicable new approach directives within the European Union
CENELEC
Comite’ Europeen de Normalisation Electrotechnique; the European electronics
organization that determines standards and testing to ensure safe operation of
electrical instrumentation in hazardous areas
Chroma I/O
Chromatographic Input/Output PCB; provides the interface between the analog
domain of the gas chromatographic analyzer and the digital domain of the
controller
components
peaks, parameters or ratios that are being measured or calculated from a
chromatographic analysis
concentration
the amount of a specific substance within a sample
CPU
Central Processing Unit; controls the analyzer and collects and manipulates the
data
cursor keys
front panel control keys marked with directional arrows
DCS
Distributed
Control
System
Data Package
application-specific engineering information (such as component tables, function
tables, chromatograms, and temperature, pressure and flow settings) shipped
with each analyzer
default values
assigned parameters the controller will assume unless the operator redefines the
values
detector
random electronic signals picked up by a sensing device in the absence
background
of valid measurable input (see “noise”)
noise
