Honeywell enCore Series Manual page 306

14
Gas chromatography
Process which allows the separation of a mixture of gaseous sub-
stances due to the differing distribution of its individual components
using a carrier gas (mobile phase) and separation columns (sta-
tionary phase).
Gas family
Classification of fuel gas types into groups based on their physical
and combustion properties (families, abbreviated to GF) A distinction
is made between 4 gas families. Gas families are classified in Ger-
many in DVGW Code of Practice G 260; natural gas and gas similar to
natural gas are members of the second gas family in this system.
Gas Quality Analyzers
are devices which automatically measure the superior calorific value
of gases. The superior calorific value, density at base conditions and
carbon dioxide content are calculated using the values from the
sensors.
Gas saturation
Reflects the influence of water vapor on calorific value/heat value. Val-
ues for wet (saturated) gas or partly wet (partially saturated) gas are
lower than those for dry (unsaturated) gas because the total volume
consists of the components of hydrocarbons and water vapor. The
instrument do not analyze water vapor. The determination of the
actual water vapor content must, for example, be obtained from mois-
ture or dew point measurements. The results are therefore calculated
for three assumed standards (dry/wet /partly wet) of water vapor.
Ground loop
Grounding the devices may create ground loops since the cable
screens create additional connections if they are connected to both
sides. A ground loop is electric cabling closed to create a loop. In the
event of low-frequency error currents, an undesirable voltage drop
occurs in the signal path and an interference signal is added to the
signal as a result of the impedance of the loop.
Grounding
Grounding is the general term used for the highly conductive
connection to a reference potential, for example, to the earth which is
also conductive. This device connection is used, among other things,
to prevent incoming and outgoing interference as described in the
EMC directives and allows various electrical devices and equipment
to be operated with a joint reference potential.
GasLab Q2 User Manual (N )
Glossary
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