Emerson Rosemount CT5400, Инструкция по установке, эксплуатации и обслуживанию

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The Main menu is used to access the software routines and screens that are used for
calibration and maintenance. Five options are presented ( Figure 6-1 ). For more information
about the options on the Main menu , see Section 4.9 .
On the Main menu , and can be used to scroll between the menu options (A). When
the option you want is highlighted ( GAS SERVICE is the example shown in Figure 6-1 ), press
to go to the first screen of that software routine.
6.3 Calibration
Calibration flows the known cylinder gas through the analyzer and then adjusts the
readout until the measurement matches the cylinder. This adjustment is then applied to all
measurements until the next calibration. There are two circumstances in which you may
want to calibrate.
1.
After you verify (see Chapter 5 ) and find that the analyzer readings are outside of
tolerance
2. At regular intervals, such as once a day or once a shift
6.3.1 Zero calibration
Zero calibration is calibrating the analyzer so that when no sample gas is flowing through
it, the gas concentrations measured by the instrument are zero. Zero calibration is done by
calibrating the analyzer measurements against a known sample gas using the following
procedure:
Prerequisites
Run the analyzer at a stable temperature for at least thirty minutes prior to commencing
this procedure.
Use nitrogen gas of instrument gas purity as the zero calibration gas.
Procedure
1. Make sure that a pressure regulator is connected to the nitrogen gas bottle.
2. Connect a hose from the nitrogen gas bottle through a T-piece to the sample supply
port on the rear of the analyzer. Connect an excess flow line to the unused port on
the T-piece and route the excess flow line to a suitable extractor.
3. On the display controller of the analyzer, browse to the Main menu as described in
Section 4.9 .
Gas Calibration Procedures
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