COSA Xentaur Hygrocontrol Type 72 - Manual (Page 13)

Series 72 Manual page 9
1) A calibration with saturated LiCl-solution of 11.3%
will replace the former 10%-value.
2) A calibration with saturated NaCl-solution of 73.6%
will not replace the two former values at 65% and 80%.
7.3. Entering "CALIB"
From normal measuring mode you enter the main program area by pressing
"E". The display now shows "LIST". Pressing "M" now switches over to "CALIB"
and the first line of the display shows "0000" with a flashing first digit. It is
necessary now to enter the password by using " " to change the digit which is
flashing and " " to go to the next decimal. If the displayed number matches the
desired password - one digit always flashes - then pressing "E" will bring you
into the program. The display shows "CHANGE" as the first submenu of
"CALIB". By pressing "M" the other submenus of "CALIB" may be chosen.
7.4. Calibration Procedure ("CHANGE")
If the calibration chamber is fixed to the probe and filled with the solution you
want to calibrate with, the calibration is initiated by "E".
The first line of display will show the measured rel. humidity, the second line will
propose a standard fixpoint which is closest to the actual measurement. If this
proposal does not correspond to the solution, you may change it by hitting "M"
as often as necessary to give the display you want.
If a humidity value you want to calibrate, is not in the proposal list, you may
choose "OTHER" and acknowledge with "E". Now the humidity value is shown
with a flashing first decimal, and adjustment may be done, to achieve the
display you need, by using " " and " " buttons. " " increases the flashing
decimal, " " steps over to the next one. If the desired value is in the display,
press "E". Now a safety check is seen in the form of "N ok Y". Pressing "M" will
jump back to "OTHER", pressing "E" will step into the calibration procedure, as
explained next.
Now pressing "E" will start the calibration. The display shows in the first line
(flashing) the rel. humidity measured, and in the second line (alternating) the
chosen point and a number corresponding to the actual oscillator frequency of
the sensor. This display allows you to see, when stability of humidity in the
chamber is achieved.
When stable conditions are reached, the flashing display ends and you will see
the symbols "Y" and "N". If you want to accept this calibration, you hit "E" now, if
you want to reject it, you hit "M". In both cases the program jumps back to
"CHANGE". If "E" was "E" hit the new calibration is kept in memory. If "M" was
hit the former calibration point is still in memory and no change occured. The
time to reach sufficient equilibrium varies with the solutions and the
environmental conditions and may be 10 minutes or 2 hours.
To calibrate more points you must change the solution in the calibration
chamber. After spilling the old solution, the chamber should be cleaned with
water, and dried before filling with another solution. After closing the chamber
you may start with the next calibration.