Emerson Rosemount CX1100, Reference Manual, Page: 29 / 48

5 Calibration and maintenance
The Rosemount
™
CX1100 In Situ Oxygen Transmitter can be calibrated in the installed
position without removing the instrument from the process duct and also while the
combustion process is online.Gas is applied to the sensor through the calibration gas
fitting. New Rosemount CX1100 In Situ Oxygen Transmitter systems are factory calibrated
and are generally acceptable for initial startup and operation. High accuracy can be gained
by calibrating a system during normal operating conditions. Emerson
™
recommends
calibrating on a semi-annual to annual basis for most applications; however actual
calibration frequency may vary per process unit.
Calibrations are conducted using a two point calibration. Factory calibration uses 0.4% O
2
and 8.0% O
2
gases with a balance of nitrogen and is therefore recommended. Calibration
gases with other oxygen concentrations are acceptable. If using different calibration gas
values, additional configuration through the Rosemount CX1100 Remote Transmitter is
required. Emerson does not recommend pure nitrogen as a calibration gas.
5.1 Procedure
The calibration of the Rosemount CX1100 Probe is initiated from the Rosemount CX1100
Remote Transmitter. The Rosemount CX1100 Remote Transmitter display prompts you
with the calibration instructions.
1.
Press the x1 or x2 menu button on the Rosemount CX1100 Remote Transmitter
display to enter the probe.
2. Navigate, using Up and Down buttons to
Setup
; press Enter.
3. Navigate to
Cal Gas
values; press Enter.
4. Navigate to
Cal Gas 1
and press Enter twice to highlight the value setting.
5. Use the Up and Down buttons to set
Cal Gas 1
value and Left and Right buttons
to move to decimals setting.
6. After setting the correct value, press Enter and press Left to go to the Calibration
Setup for
Cal Gas 2
,
Gas time
, and
Purge time
settings.
7. After setting the values (0.4% O
2
, 8.0% O
2
, and 300s are the defaults), press Left to
go up to the Calibration submenu.
8. Navigate using the Up and Down buttons to
Calibration
and press Enter to start.
9. Follow the instructions on the display, manually applying calibration gases (0.4% and
8.0% O
2
at 5 SCFH are recommended) to the calibration port.
10. After the calibration is finished, press Left and use the Up and Down buttons the
check the current and previous 10 calibrations log.
After completing the procedure, the Rosemount CX1100 software calculates new
calibration values and determines whether they meet an acceptance criteria. If successful,
the new calibration values automatically replace the previous values. In the event the
Calibration and maintenance
Reference Manual 23