JENCO EC3840, Руководство по эксплуатации

Страница: 7 / 13

6
3. Standard solution of 111.9mS at 25
℃
: Accurately weight out
74.264 grams of research grade dried Potassium Chloride
(KCL). Dissolve in 1000ml of distilled water.
[Note:
You can store the remaining solution in a plastic
container for one week but the air space between the cap and
the solution must be kept to an absolute minimum. Storing the
excess solution below 4
℃
can increase the storage life. If you
have any doubt of the accuracy of the stored solution, a fresh
batch should be prepared.
]
B. Calibration
Calibration setup contains five sections: TDS, Cell, Temperature
Coefficient, Temperature reference and Conductivity Calibration. To
access these sections:
1.
Connect the conductivity probe 3840P to the unit and turn the
unit on. The screen will display
CELL and the cell constant of
the conductivity probe.
2.
Allow temperature reading to stabilize, press “ Cal ” key to
enter the calibration mode. CAL appears on the LCD. Press
“ Mode ” key to sequentially display the following sections:
[Note: Press “ Enter ” key to accept any values changes in
each section and automatically advance to the next section. If
there are no changes, the unit accepts the current value and
proceeds to the next section.
]
TDS
TDS is determined by multiplying conductivity (mS) by a TDS
factor. The default factor value is 0.65. To change the TDS
factor, use the up and down keys to adjust the value between
0.30 and 1.00. Press “
Enter ” key to save the new value, or
press “ Mode ” key to cancel the change and display the CELL
screen.
CELL
The second screen will display CELL and the current cell
value. The default cell value is 0.50 and is displayed in the
lower right of the screen. The unit allows a variance of +/-0.15
before displaying an error message. The cell value can’t be
adjusted at this screen; calibrating conductivity is the only
way to adjust the cell constant. Press “
Enter ” key to reset the
cell constant to 0.50 and display the Temperature
Coefficient screen.