Filter
Top Products
Section 4
Page 77
pH Sensor
4.9 pH Sensor
pH sensor function degrades over time, even under ideal conditions, and
therefore require periodic replacement. The pre-amplifier junction box is
provided to allow for fast, easy replacement of the pH sensor. For extra strain
relief the pH cable that leads to the instrument should pass through the water-
tight strain relief adapter.
Since the pH reading must be compensated for temperature variations, a
temperature sensor is built into every pH electrode. After installation, the pH
sensor must be programmed and calibrated.
4.9.1 Programming the pH Sensor
1. From the Main Menu Select OPTIONS>ADVANCED OPTIONS>DATALOG.
2. Highlight SELECT INPUTS using the up and down arrow soft keys and then
press the
SELECT soft key.
Note: If logging is enabled on any
channel, an arrow in front of the
channel name will appear to signify
that the channel is logged.
3. Highlight pH / mV using the up and down arrow soft keys, then press the
SELECT soft key.
4. Select pH in the Item to Edit menu using the pH soft key.
5. Press the
CHANGE CHOICE soft key to cycle between “Logged” and “Not
Logged”, then press the
ACCEPT soft key.
6. Enter a logging interval using the numeric keypad, then press the
ACCEPT
soft key. Valid logging intervals are shown on the status bar along the
bottom edge of the display.
7. Select another channel to configure or press the
RETURN soft key to
back up one step or press the
MAIN MENU function key to return to the
Main Menu.
4.9.2 Calibrating the pH Sensor
Once the pH sensor is wired and programmed, calibrate the pH sensor.
Calibrating the pH sensor requires a thermometer and any two of the following
buffer solutions: 4, 7, or 10 pH.
The pH probe is an application sensitive device. When used in harsh
environments, the accuracy and life expectancy of pH probes can decrease
considerably.
Probes must be calibrated to the flow meter each time they are cleaned
or replaced. Regular inspection and comparison to a hand-held pH meter can
help determine the optimum cleaning and calibration schedule for your
application.
Note: Before calibrating the pH
probe make certain the probe and
buffers are at ambient temperature.
1. From the Main Menu, select OPTIONS > ADVANCED OPTIONS >
CALIBRATION > pH.
2. Place the pH probe into the first buffer solution, then press any key
to continue.
3. Enter the temperature of the first buffer solution using the numeric
keypad. Press the
ACCEPT soft key to continue.