Emerson Rosemount CT4400, Reference Manual

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CALIBR PARAMS allows configuration of the purge time for Gas Calibration.
VERIFY PARAMS allows configuration of the purge time for Gas Verification.
STREAM SWITCH not an option available for the Rosemount CT4400 analyzer.
Pressing the Back key will return to the previous screen. Pressing the Home key at
any time will return to the Main Menu screen.
6.3 Calibration
Calibration flows the known cylinder gas through the analyzer and then adjusts the
readout until the measurement matches the cylinder. The analyzer then applies this
adjustment to all measurements until the next calibration. There are two circumstances in
which you may want to calibrate:
1. After you verify gas concentrations (see Verifying gas concentrations ) and find that
the analyzer readings are outside of tolerance.
2. At regular intervals, such as once a month.
6.3.1 Zero calibration
The zero calibration procedure adjusts for any zero offset in the measurement. 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.
Procedure
1. Use nitrogen gas of "instrument gas" purity as the zero calibration gas.
2. Ensure that a pressure regulator is connected to the nitrogen gas bottle.
3. Connect a hose from the nitrogen gas bottle through a T-piece to the sample supply
port on the rear of the analyzer.
4. Connect an excess flow line to the unused port on the T-piece and route the excess
flow line to a suitable extractor.
5. On the display controller of the analyzer, browse to the Main menu as described in
Gas service menu definitions .
Gas calibration Reference Manual
January 2020 00809-0100-4244
50 Rosemount CT4400