PART THREE - OPERATION
SECTION 5 - ANALYZER CALIBRATION
Rev. 6-501
Model P53 pH/ORP Analyzer (universal-mount 1/2 DIN)
57
S
ECTION
5
5.1 Important Information
Calibrate Periodically
☞
Temperature-corrected
pH Measurement
☞
Four methods are available for pH calibration (Section 5.2).
To calibrate ORP, use only the 1-POINT SAMPLE method
described in Section 5.3. The mA value for each analog
output can also be calibrated (Section 5.4).
To maintain best measurement accuracy, periodically cali-
brate the analyzer. Performance of the pH or ORP sensor
slowly degrades over time, eventually causing inaccurate
readings. The time period between calibrations, and the
rate of system drift, can vary considerably with each appli-
cation and its specific conditions.
Calibration Tip!
Establish a maintenance program to
keep the sensor relatively clean and the analyzer cali-
brated. The daily, weekly or monthly intervals between
performing maintenance will be influenced by the char-
acteristics of the process solution, and can only be
determined by operating experience.
The analyzer is factory-calibrated for accurate temperature
measurement. It will provide pH readings that are automati-
cally corrected for temperature changes when the analyzer:
•
Receives a temperature signal from a pH sensor that
has a built-in temperature element (all GLI Differential
sensors) or from an external temperature element.
•
Has been correctly set for the type of temperature
element being used for automatic compensation.
NOTE:
When the passcode feature is enabled (Section
4.6), you must successfully enter the passcode
before attempting to calibrate the analyzer.
Also, an in-progress calibration can always be
aborted by pressing the ESC key.
After the “ABORT:
YES?” screen appears, do one of the following:
•
Press
ENTER key
to abort. After the “CONFIRM
ACTIVE?” screen appears, press
ENTER key
t o
return the analog outputs and relays to their ac-
tive states (MEASURE screen appears).
•
Press
×
×
or
Ø
Ø
key
to choose “ABORT: NO?” screen,
and press
ENTER key
to continue calibration.
ANALYZER CALIBRATION
