Metex 2200C Conductivity Analyzer/Controller - Manual (Page 14)

Model 2200C Page 12
5.0 START-UP AND OPERATION
5.1 Password
5.1.1 To enter the menu press CALL and the PASSWORD LED will illuminate. If the
password feature has been disabled by the dip switch, TEST will be the first menu
item illuminated when the CALL button is pressed. With each press of CALL button
you will step through the menu. When the last item, ALARM LOW is reached the
menu wraps around to TEST. If you have enabled PASSWORD by placing DIP
Switch No. 2 of Bank S1 in the off position you must enter the password “6” when
PASSWORD is indicated, if you wish to change any stored value. If the password
is enabled and you do not enter the correct password. All the items in the menu will
be read only.
5.2 Calibration
5.2.1 To calibrate the instrument you will need:
• a buffer solutions of known conductivity
• a beaker of clean water
The 2200C requires a one point calibration, using a conductivity buffer solution. It is
possible to calibrate the unit to the process conductivity. This can only be done
when a sample is taken and measured with a certified lab unit. The process of
calibrating is the same for both methods. If you are calibrating using the sample
method, substitute the certified lab units reading for the know conductivity, and
leave the cell installed in the process. The recommended calibration procedure is
with a certified lab meter.
To calibrate the 2200C in Manual Calibration Mode proceed as follows:
a) Enter the menu by pressing CALL. Proceed by pressing CALL until the
CALIBRATION LED illuminates.
b) Remove the protective cap from the cell, rinse it in clean water, and place it in
the buffer solution. The display will change as the controller measures the
conductivity and the temperature of the buffer solution. The display may flash
which indicates that the instrument is receiving an unstable signal from the cell.
The display will come to a rest and should display a value close to the buffer
solution. If the value on the display is greatly different from the value of the
buffer solution, this indicates that the current calibration is not very close to the
actual value, or the buffer solution is contaminated. If you are confident in your
buffer solution proceed by using the arrow keys to correct the display to read
the actual value of the buffer. Press ENTER. The display will flash until
ENTER is pressed again to confirm the value.