Rosemount 7D, Инструкция по эксплуатации

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4
O
PERATION
748221-L Rosemount Analytical December 2000 23
Model 7D Thermal Conductivity Analyzer
4.1 ROUTINE OPERATION
First, complete startup per Section Three. If the analyzer has more than one range,
turn front panel RANGE Switch to desired position. Admit sample gas at the
previously selected flow rate. The analyzer will continuously indicate the
concentration of the measured component in the sample stream.
A calibration curve can be used to convert meter or recorder readings to concentration
values. Typical calibration curves are supplied for standard ranges. Calibration
curves for special ranges are available as options.
To avoid use of a calibration curve in an application where it would otherwise be
required, the analyzer may be equipped with an optional linearizer board. If so, the
linearizer board is factory set for a given range only, and is not usable on another
range. Note that a linearizer is usable only if nonlinearity at midscale does not exceed
20% of fullscale.
4.2 RECOMMENDED CALIBRATION FREQUENCY
Provided that the instrument remains in continuous operation with power on, it is
necessary only to calibrate once a week, by the procedure of Section 3.4.
To restart the analyzer after power turn-off, repeat the startup procedure of Section
3.3 and calibrate per Section 3.4.
4.3 SHUTDOWN
Before turning off sample gas, and flowing reference gas, if used, disconnect power
from the analyzer. This precaution minimizes the risk of filament damage.