Metex 2200R ORP Analyzer/Controller - Manual (Page 16)

Model 2200R Page 14
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
3.5.1 All ORP systems must be calibrated when first installed, and re-calibrated each time
that a new probe is installed. Calibration should be performed regularly to ensure
optimal performance. The frequency of calibration can only be found through the
operators experience, as all processes will vary.
5.2.2 To calibrate the instrument you will need:
• two buffer solutions of known ORP
• a beaker of clean water
Commonly used buffers have values of 200mV and 600mV. Both are available
from AquaMetrix
To calibrate the 2200R proceed as follows:
a) Enter the menu by pressing CALL. Proceed by pressing CALL until the
CALIBRATION LED illuminates.
c) Remove the protective cap from the probe, rinse it in clean water, and place it in
the first buffer solution. The display will change as the controller measures the
ORP of the buffer solution. The display may flash which indicates that the
instrument is receiving an unstable signal from the probe. 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.
d) Rinse the probe in the clean water, and place it in the second buffer solution.
Repeat the same process as above to accept the second value.
d) The system is now calibrated. Press RUN to place the instrument on line or
use the CALL key to proceed to other menu items.