bluelab OnePen User Manual page 6

To calibrate the pH
Excluding first use, gently clean the OnePen™ Probe with Bluelab Probe Cleaner
and rinse well in fresh tap water.
See section 3.2 on how to clean the probe (the probe does not require cleaning before
the first use but may require 24-hour hydration in KCl).
In several separate plastic containers, prepare a small amount of:
fresh tap water
•
pH 7.0 calibration solution.
•
pH 4.0 or pH 10.0 calibration solution.
•
pH 7.0 calibration
1. Press "O" to turn on.
2. Select pH/Temp measurement mode
via the "CAL" button. Make sure pH
reading is displayed on the main
display.
3. Place the probe in the pH 7.0
calibration solution. Always
calibrate pH7 first!
4. Wait a few minutes for the probe to
come to the same temperature as
the solution.
5. To calibrate pH7 hold the "CAL"
button until "CAL" displays, then
release.
6. Wait until •'s stop flashing from left
to right, "7" stops flashing and "PASS
PH7" displays.
7. Now you can calibrate to pH 4.0 or
pH 10.0