ELTRA CS-2000, Service Manual

Page: 80 / 160

Adjustments
80
TP 23: Output section [4]
4.2.4 Base line adjustments.
See also chapter “
Check base lines
”.
When the IR module (rack) is removed from the analyzer, it can be powered on the desk by a
24VDC power supply connected to J1 of the IRC board. The power supply should normally be
capable to supply a current of 5A.
If a lower current power supply available, in order to prevent the temperature control from taking
high current from the power supply, set a jumper to position 2 of the connector J1. In this case a
24V / 1A power supply will be enough.
CAUTION:
Remember to remove the jumper from position 2 before reinstalling the IR module into the
analyzer, otherwise the thermostatic control will not work.
4.2.5 Infrared cell board IRC1.x sections assignment
board sections [4] [3] [2] [1]
4 cells IR module Hi S Lo S Hi C Lo C
3 cells IR module S Hi C Lo C
3 cells IR module Hi S Lo S C
2 cells IR module S C
2 cells IR module Hi C Lo C
2 cells IR module Hi S Lo S
1 cell IR module C
1 cell IR module S
Explanations
–
Lo C: Low carbon range (long C path)
–
Hi C: High carbon range (short C path)
–
Lo S: Low sulfur range (long S path)
–
Hi S: High sulfur range (short S path)
–
C: single carbon range (single C path)
–
S: single sulfur range (single S path)
The preamplifier connectors of the cells are of course connected to the corresponding sections
according to the above assignment list. (4-pin module connectors).
Example
A three cell module with a low carbon, a high carbon and a sulfur cell has
–
the low carbon signal on section [1], the LoC preamp is on X1
–
the high carbon signal on section [2], the HiC preamp is on X2
–
the Sulfur cell signal on section [3], the S preamp is on X3
The base line adjustments are done by adjusting the gain of the preamplifier of each IR cell in
the IR module (rack). The gain adjustment is done by turning the trimmer which is inside of each
preamplifier. The base line voltages can be measured on the following test points: