7
to stabilize if a temperature sensor is connected, or manually
change the temperature reading with the
up
and
down
keys if no
temperature sensor is connected.
5. Press and hold the
Stand
key for 2 seconds to calibrate. The unit
will immediately be calibrated to the first point. The buffer used for
the first point will remain lit on the display while the remaining two
buffers start to flash. The unit is ready to be calibrated using the
second buffer solution.
• To complete a one point calibration, press the
Mode
key after
successful calibration using the first buffer.
6. Rinse the pH and temperature (if applicable) sensors with distilled
water and immerse in the second buffer solution (either 4.00/4.01
or 9.18/10.01). Allow sufficient time for the pH measurement
to stabilize. Also allow the temperature reading to stabilize if
a temperature sensor is connected, or manually change the
temperature reading with the
up
and
down
keys if no temperature
sensor is connected.
7. Press the
Slope
key to calibrate to the second point. The unit will
immediately be calibrated to the second point. The buffer used
for the first and second point will be lit on the display, while the
remaining buffer will start to flash. The unit is ready to be calibrated
using the third buffer solution.
• To complete a two point calibration, press the
Mode
key after
successful calibration using the first two buffers.
8. Repeat steps #5 and #6 for the remaining buffer solution. The
pH1000A will automatically exit the pH calibration mode after
successful calibration with the third buffer.
VIEWING THE ELECTRODE EFFICIENCY AFTER CALIBRATION
The pH1000A calculates and compensates for the pH electrode slope
deviation corresponding to the values of the three calibration buffers.
After calibration, press and hold
Meas. / Effic.
key for 5 seconds to
display the new electrode efficiency.
Electrode efficiency can be converted into a mV/pH slope value based
on the following equation, with -59.16 mV/pH being the theoretical
Nernst Slope:
• Electrode Efficiency = Observed Slope * 100
-59.16
mV/pH
A single electrode efficiency will be displayed after a single point
calibration. This efficiency will always equal 100%, as the theoretical
Nernst Slope will always be used for the observed slope. This is why
YSI recommends at least a two point calibration.