Emerson Rosemount CCO 5500, Reference Manual

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6. Use the arrow keys to enter the desired value for this digit. Press ENTER to select the
displayed value; the cursor moves to the second digit. Select the value for the
second digit and press ENTER. Continue this process for each digit of the security
code.
When the fourth digit is correctly entered, the processor enters Mode 5 .
7. When in Mode 5 , select Calibrate using the keypad arrow keys; press ENTER to access
the Calibrate menu.
8. Use the arrow keys to select SET DETECTORS ; press ENTER.
The display shows the D1 and D2 detector levels.
CAUTION!
If the analyzer is not in SET UP mode, the gas cell at the source unit periodically
interrupts the IR beam and make alignment difficult.
9. Adjust the receiver alignment, using the adjusting nuts, Figure 3-2 . Adjust in one
plane, then in the other.
As a rule, the D2 detector level is affected to a greater extent by adjustment in one
particular plane. The D1 detector level is affected more by adjustment in the other
plane.
10. Make sure the maximum possible values of both D1 and D2 are reached. After you
achieve alignment, tighten the locking nuts.
Note
The alignment of the receiver unit is important. Make sure to obtain the maximum values of
D1 and D2.
11. If the displayed detector level is below 5000, increase the gain at the control unit to
between 12000 and 14000.. If the detector level is above 15000, reduce the gain to
between 12000 and 14000.
Refer to Section 3.5 for details.
12. To fine tune the alignment, repeat adjustments of Step 9 at the source unit. Again,
make sure the values of D1 and D2 are appropriate. Lock the source unit in place
when the maximum values are achieved.
13. When you have properly completed the alignment, there is rarely any need for
further alignment adjustments.
3.5 Detector levels
The gain of the detector signals is set in two locations:
1. In the receiver, two potentiometers set the gain. Refer to Section 3.5.1 .
Configuration and startup
Reference Manual 29