ABB Totalflow NGC8206 Manual Del Usuario página 289

TERM
Noise
Nonane (C9H20)
Non-hazardous area
Non-Persistent
Normal Butane
Normal Pentane
Normalization of
Component Mole
Percentages
Normally Closed
2103650-001 – rev. AB
An undesirable electrical signal. Noise comes from external sources
such as the AC power line, motors, generators, transformers,
fluorescent lights, soldering irons, CRT displays, computers, electrical
storms, welders, radio transmitters, and internal sources such as
semiconductors, resistors, and capacitors. Unwanted disturbances
superimposed upon a useful signal that tends to obscure its information
content.
A hydrocarbon (Alkane) flammable colorless liquid with nine carbon
atoms.
Area in which an explosive gas atmosphere is not expected to be
present in quantities such as to require special precautions.
Refers to data that is no longer available after a Warm Start.
An aliphatic compound of the paraffin series having the chemical
formula of C4H10 and having all of its carbon atoms joined in a straight
chain.
A hydrocarbon of the paraffin series having a chemical formula of
C5H12 and having all its carbon atoms joined in a straight chain.
The exact amount of sample which is injected onto the columns of the
chromatograph must be a very reproducible volume in order to give
consistent values for the resulting calculated Btu. The calculation
controls the volume, temperature and pressure of the sample to be
injected by a very simple means. A few seconds before the sample is
actually injected, the flow of sample through the sample valve injection
loop is stopped by automatically shutting the sample shut-off valve.
This allows the pressure of the sample in the sample loop to bleed
down to atmospheric pressure. Since the temperature is controlled and
the size of sample loop does not vary then the only change possible in
sample size is related to variations in atmospheric pressure.
Atmospheric pressure does vary with the weather and in order to
compensate for this or any other slight sample size change, the mole
percentages of each component are adjusted to equal a total of 100%
through a calculation called normalization.
The values in mole percents are determined by the chromatographic
analysis and then totaled to a value that is near 100%, which is called
the unnormalized total. The unnormalized total is divided by 100% and
the resulting factor is then multiplied by the mole% value for each
component. This calculation will adjust each component's mole% in the
correct manner as to result in a new total of exactly 100%. The
calculation also checks to see if the unnormalized total is out of a
specified range for alarm purposes. This is an overall performance
check to determine if the chromatograph has some problem or has
drifted out of calibration.
Designation which states that the contacts of a switch or relay are
closed or connected when at rest. When activated, the contacts open
or separated.
DEFINITION
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