Emerson ROSEMOUNT OCX 8800 - Manual (Page 40)

Instruction Manual
IM-106-880, Rev 1.0
January 2007
OCX 8800
2-20
8. Install an air line between the instrument air outlet fitting on the
electronics housing and the control air inlet fitting on the air-operated
solenoid valve.
9. There are three settings that need to be specified to set up the blowback
option. These are the blowback interval, duration, and purge time.
Interval - Length of time between blowback events.
(60 minutes recommended.)
Duration - Length of time blowback air is activated.
(5 seconds recommended.)
Purge - Length of time after blowback is complete before
oxygen/combustibles readings are considered valid.
(Set as required by the application.)
These settings are available through HART from the DEVICE SETUP >
DETAILED SETUP > OUTPUT CONDITIONS > BLOWBACK menu.
INITIAL STARTUP Observe the following Caution and Note. Refer to Section 3: Configuration
and Startup, for OCX 8800 startup information.
NOTE
During outages, and whenever possible, leave OCX 8800 units running to
prevent condensation and premature aging from thermal cycling.
Upon completing installation, make sure that the OCX 8800 is turned on and operating prior
to firing up the combustion process. Damage can result from having a cold OCX 8800
exposed to the process gases.
If ducts will be washed down during outages, make sure to power down the OCX 8800 units
and remove them from the wash area.