ELTRA CS-2000, Service Manual

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Adjustments
75
Remark:
Due to a few failures of the flow sensors, almost exclusively with users who analyse samples
with high sulphur and high moisture or regularly treat their samples with acid, we concluded that
the reason of the failures should be of chemical nature i.e. sulphuric acid and other acids
damage the sensor.
The solution is to prevent the analysis gases to get in contact with the sensors. Therefore the
sensor ports are connected with long tubes to the gas flow system. There is no gas flow through
the sensor tubes but only the pressure is sensed by the sensor.
In case of failure of a previous version sensor, it is advisable to replace it by the new version. In
this case the part numbers of the complete assemblies should be used for ordering. In case the
analyzer has already the new version sensor, the order should include the spare part number.
See drawings below and chapter
“
Ordering numbers
”.
Fig. 59: New flow sensor
Fig. 60: Old flow sensor
Pos : 5. 4 / 0025 Ü bersc hrift en/ELTR A 1. 1 Ü bersc hrift en/ 11 Infrar ed bas e line adj ust ments ELTRA @ 6\ mod_1369121936836_9. doc x @ 41542 @ 2 @ 1
4.2 Infrared base line adjustments
Pos : 5. 5 / 0010 ELTR A/ 0015 s er vice_i nstr uctions /CS- 2000_s er vic e/10Adj ust ments _CS- 2000/1010 Modul I nfrar ed bas eline @ 9\ mod_1425542384792_9. doc x @ 74574 @ 334434 @ 1
4.2.1 Infrared cell modification - general information
Eltra has changed the IR cell design. This modification makes the cells less susceptible to
contamination problems and makes the calibration more stable. The changes are:
The IR-4 board is modified so that now the output voltage of the cell is adjusted at 8V instead of
zero.
The voltage of each source remains unchanged at 1.75 volts as it used to be.
After this modification the peaks you see on the screen and the output voltage of the IR cell are
two different things.
The Peaks on the screen look the same way like they used to look before starting from zero
(base line) and going up positive.