Teledyne 7120 - NDIR analyzer - Manual (Page 45)

4 Operation Model 7120
4-12 Teledyne Analytical Instruments
Hard_offset_C=3015 (This is the raw DAC count of the Coarse zero
adjustment. It should read between 0 and 4095)
Hard_offset_F=2715 (This is the raw DAC count of the Fine zero
adjustment. It should read between 0 and 4095)
Current_gain = 4 (This is the gain the analyzer is on, it should read
between 0 and 9)
4.3.9 Digital Filter Setup
The 7100 analyzer has the option of decreasing or increasing the amount
of filtering on the signal. This feature enhances the basic filtering done by the
analog circuits by setting the amount of digital filtering effected by the micropro-
cessor. To access the digital filter setup, scroll through the menu and select
FILTER. Press the Enter key to see the following screen:
Enter Digital
Filter: 4
The number on the second row can be adjusted from 0, minimum digital
filtering, to 10, maximum digital filtering. The default setting is 4 and that should
suffice for most applications. In some applications where speeding the response
time with some trade off in noise is of value, the operator could decrease the
number of the digital filter. In applications where the signal is noisy, the operator
could switch to a higher number; the response time is slowed down though.
10 to 90% response time on the different settings to a step input is
shown below. This response time does not include the contributions of the bench
sampling system and the preamplifier near the detector.
Setting 10-90% Response
(seconds)
0 2.5
1 5
2 10
3 20
4 40
5 80