Rosemount OCX 8800, Instruction Manual

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Instruction Manual
IM-106-880, Rev 2.1
April 2017
OCX 8800
3-7
Blowback Purge Time - Length of time after blowback is complete
before oxygem/combustibles readings are considered valid (Set as
required by the application).
Initiate Blowback - Initiates a blow back event manually.
Configuring Blowback with the LOI
1. Use the "Z" pattern to enter the LOI menu tree.
2. From the SYSTEM menu, select Blow Back .
3. From the Blow Back menu, select Blow Bk Enable . Select Yes to
enable blowback. Also set the following parameters:
Blow Bk Intrvl - Length of time between blowback events. Range is 0
to 32,000 minutes. Default is 60 minutes. 60 minutes is recommended.
Blow Bk Period - Length of time blowback in activated. Range is 1 to 5
seconds. Default is 2 seconds. 5 seconds is recommended.
Blow Bk Purge - Length of time after blowback is complete before
oxygem/combustibles readings are considered valid. Range is 0 to 500
seconds. Default is 88 seconds. Set as required by the application.
Force Blow Bk - Initiates a blow back event manually.
CALIBRATION VERIFY
FEATURE
The calibration verify feature flows one or more calibration gases to verify the
analyzer is reading correctly. The calibration verify feature flows each
calibration gas on demand to verify calibration, but does not change the slope
or constant of the current calibration. This function uses the same gas flow
and purge times from the basic calibration setup.
The calibration verify feature is only valid if the OCX 8800 is supplied with
calibration solenoids and the solenoids have been activated.
Performing a Calibration Verify with the Field Communicator - HART
1. Use the 375 Field Communicator or AMS software to access the HART
menu.
2. From the DEVICE SETUP menu, select DIAG/SERVICE .
3. From the DIAG/SERVICE menu, select CALIBRATION .
4. From the CALIBRATION , select CAL VERIFY . Select Verify
Calibration . From this menu, select the functions as follows:
Flow High O2 Gas - Flows the high O2 test gas for the time specified in
the calibration setup.
Flow Low O2 Gas - Flows the low O2 test gas for the time specified in
the calibration setup.
Flow High COe Gas - Flows the COe test gas for the time specified in
the calibration setup.
During the Calibration Verify function the analog output signals will track the oxygen and
combustibles readings. To avoid a potentially dangerous operating condition, the OCX
8800 must be removed from the automatic combustion control loop before performing the
Calibration Verify procedure.