Emerson Rosemount CCO 5500, Reference Manual

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measurement is made. After you define the wet or dry, you need to define the Analog Input
values; set the 4 mA and 20 mA values. If the oxgyen level is relatively constant through all
firing conditions, you may use a fixed keypad input.
With an integrated system, you can take the oxygen data to the instrument via the serial
data line.
Note
If normalization is not required, you must set the normalizing parameters for oxygen in the
instrument.
Pressure
To correct the data to a standard pressure, normally 14.7 psi (101 kPa), you must
determine the pressure at the point of measurement. If the flue pressure is relatively
constant through all firing conditions, then you may use a fixed keypad input. If the
pressure, is not constant, measure it and bring it into the instrument via the 4-20 mA
analog input within the processor.
Note
If normalization is not required, set the normalizing parameters for pressure in the instrument to
14.7 psi (101 kPa)(Standard Level and Keypad Input).
With an integrated system, you can take the pressure data to the instrument via the serial
data line.
Water Vapor
An across the duct monitor measures the gas concentration under wet conditions. Unlike a
sampling system, the gas has not been preconditioned in any way before you make a
measurement.
When the water vapor is at a relatively fixed level, set the standard level to DRY to
normalize it to dry conditions. Use a fixed value in the keypad option representing the
expected water vapor produced for the fuel type. If the measurement is not to be
normalized for water vapor, set the standard level to
WET .
With an integrated system, you can take the water vapor data to the instrument via the
serial data line.
4.10.6 Reset averages
Note
Resetting averages causes the rolling average data to be cleared from memory.
Operation
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