Katranji CT-6821 User manual

Pen Type pH & Conductivity Meter
Model: CT-6821
User Manual
Operating Instructions:
Pull out the cap before using, Do not Screw it!
*Power ON/OFF Feature
1. Press ON/OFF key to turn the Meter On and Off.
2. The Meter will shut OFF automatically if there is no operation in 5 minutes.
*Self-Checking Feature (Executing the function automatically after the meter is power on each time)
1. Press the ON/OFF key to turn on the meter, Self- Checking program will be auto-started with full
screen display.
2. The type of the meter will be displayed: 6821, then, the meter is ready for use.
3. The default mode is pH mode after the date of the manufacture.
4. The test mode will be same as the previous use.
*pH Mode
1. Press the ON/OFF key for 3 seconds, until the “pH” display on the screen.
2. Then press CAL to confirm, and the meter is ready to test in pH mode.
*ORP Mode
1. Press the ON/OFF key for 3 seconds, until the “pH” display on the screen.
2. Press HOLD key to select “ORP” on the screen.
3. Then press CAL to confirm, and the meter is ready to test in ORP mode.
*Backlight Mode
1. Press the ON/OFF key for 3 seconds, until the “pH” display on the screen.
2. Press HOLD key to select “LED” on the screen.
3. Then press CAL to confirm the backlight mode.
4. Power off the meter to close the backlight mode.
*Hold Feature
Press HOLD to freeze the current reading, and ‘HOLD’ will be appeared on the LCD. Press HOLD again to
release the hold mode.

*Restore factory defaults
1. If the meter is out of order, Press the HOLD key for 10 seconds, until the “CLR” display on the
screen, release the HOLD key and the factory setting is ready.
2. The meter needs to recalibration for pH measurement after the factory setting, but can be used
directly for ORP measurement.
* Automatic temperature compensation (ATC)
The product is capable of measuring with automatic temperature compensation when “ATC” displays on
the screen.
*˚C/˚F Interchangeable
The default mode is ˚C, press CAL key to switch to ˚F.
* Calibration
pH calibration
Prepare for 4 measuring glasses to calibration, 1 measuring glass for water and 3 measuring glasses for
pH buffer solution (pH4.0, pH6.8, pH9.1).
Please be aware of the order of the pH buffer solutions:
First: pH6.8, second: pH4.0, third: pH9.1
Over range Reminder
There will be “1- - .-”on the display if the pH value is under 0 or over 14;
There will be “1- - .-”on the display if the ORP value is under -500mV or over +500mV;
There will be ‘L’ or ‘H’ on the temperature display area if the temperature is under 0˚C or over 50˚C.
*Low Voltage Reminder
The battery sign will be appeared on the display when battery replacement is needed.
MAINTENANCE
Keep the glass electrode clean, and cover with the protection cap when not in use. Be aware of the
damage of the electrode when using it. Products should be kept and stored in a cool, dry place away from
direct sunlight.
NOTE
1. Please operate the meter under the guidance of professionals.
2. Soak the electrode into the distilled water or purified water for 5 –30 minutes to activate before
use.
3. Please use the standard buffer solutions for pH calibration, and operate it by the calibration steps
shown above. DO NOT press CAL key in NON calibration mode, it may cause the calibration Error.
4. The pH buffer powder should be fully dissolved in water (250ml).
How to make pH buffer solution
There are 3 pH buffer powder supplied with the meter when you buy them, each powder should be fully
dissolved in water (250ml). DO NOT use the metal containers.
Take the formulation of pH 6.8 buffer solution for example:
1. Prepare a plastic or glass container with the volume should be equal or greater than 250ml, pour the
pH buffer powder (2 small bags in the pH 6.86 green bag) into the container.
2. Fully dissolve the powder with 250ml distilled water.
Tag the three buffer solutions when finish. (Time, and pH value)
The buffer solutions (250ml) can be used several times by divided into portions which should be kept in a
cool and dry place (20℃-25℃). Never reuse the used portion. The electrode should be fully covered by
buffer solution when calibration.