Measuring Mode
The measuring mode is on by default when you turn on the device. The
measuring mode tells you the pH value and the environmental temperature. Just
immerse the electrode in the tested solution and you will get the pH value.
Battery
When the icon
appears at the right corner of the LCD display, it is time to
change the battery. Remember to take out the batteries if you will not be using the
device for a long time.
ON/OFF Hold Button
a) Press the button to turn on the device.
b) Press the button again to lock the current reading.
c) To turn off the device, press and hold the ON/OFF button.
Button
a) In measuring mode, press and hold the button for 3s to enter calibration
mode.
b) In calibration mode, press the button to increase the value; press and hold to
quickly increase the value.
Button
a) Press the button to turn the backlight on or off.
b) Under calibration mode, press the button to decrease the value; press and
hold to quickly decrease the value.
Auto Off
Before turning on the device, press and hold the ON/OFF button and
simultaneously and the LCD display will show APO ON or APO OFF. Press the
ON/OFF button to select APO ON or APO OFF; then, press and hold the
ON/OFF button to save the selection and exit.
a) APO ON Mode: The timing icon will appear, and the unit will shut down
automatically after 15 min if it is not used.
b) APO OFF Mode: No timing icon will appear, and the unit won’t shut down
automatically.
Temperature Unit Conversion
Before turning on the device, press and hold the ON/OFF button and
simultaneously and the LCD display will show
℃
or
°F.
Press the ON/OFF
button to select the desired unit; after that, press and hold the ON/OFF button to
save the selection and exit.
Outrange Indication
When the pH value is lower than 3.5pH, the backlight is on, indicating that the
tested solution is close to a strong acid; when the pH value is higher than 12.5pH,
the backlight is on, indicating that the tested solution is close to a strong base.
Recalibration
In the following cases, the instrument must be recalibrated.
Long-term unused electrode or new electrode.