Emerson NGA 2000 Computer Accessories User Manual


 
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NGA 2000
90003482(2) [NGA-e (MLT-Software 3.2.X)] 07/98
Conditions:
Before you start the linearization you have to calibrate the largest range of the channel
(usually range 4) with zero gas and span gas.
You have to record a raw values/setpoint values table to linearize a channel. You need
minimum 6 raw values and their corresponding setpoint values: zero, end of range and
4 intermediate values. You should take 10 to 15 values (maximum: 30) to improve the
precision of the linearization curve.
Realize the linearization:
1) Disable the linearization:
Before you record the linearization values you have to disable the current linearization
to avoid the influence from the old values to the calculation of the new curve.
Change to the line "Linearizer is" with the -key or the -key.
Press the 88 -key or the -key and select "Disabled" with the -key or the -key.
Confirm your adjustment with the 88 -key.
2) Zero and span gas calibration:
Calibrate the largest range (usually: range 4) with zero and span gas.
The method is described in 4.5 p. 4-39 and 4.6 p. 4-43 or in 5.1.1 p. 5-15 to 5-17.
3) Recording the raw values/setpoint values table:
If you have a defined gas flow, you can read each raw value in any menu display at
the top right or in the single component display.
Example:
You have got the following values for the NO-Channel of the analyzer:
No. Setpoint Value
[ppm NO]
Raw Value
[ppm NO]
1 0.000 0.000
2 217.455 266.291
3 319.620 387.709
4 428.610 517.464
5 536.760 645.199
6 636.510 757.313
7 955.395 1113.910
8 2105.560 2263.390
9 3163.860 3163.860
4) Putting the table values into the corresponding menus:
Change to the menu line "Linearization raw values..." or "Linearization setpoint
values..." with the -key or the -key.
Press the 88 -key or the -key to change to the menu "Linearization Raw Values" or
"Linearization Setpoint Values".
Select the first number with the 88 -key or the -key.
Put in the first raw/setpoint value of the table:
Select any digit with the -key or the -key and adjust the new value with the
-key or the -key and confirm the new value with the 88 -key.