Emerson Rosemount OCX 8800, Instruction Manual

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Instruction Manual
IM-106-880C, OI
Section 3: Configuration and
Startup
April 2017
Configuring Blowback with the
LOI
49
2. From the Alarm Relay/Blowback menu, select Blowback.
3. From the Blowback menu, select Blowback Enabled. Also set the following parameters:
• Blowback Interval - Length of time between blowback events (60 minutes
recommended).
• Blowback Period - Length of time blowback is activated (5 seconds
recommended).
• 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.
3.6.3 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.
3.7 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.