Appendix
I
6
0 × 0009 - 20.00 mA correspond to conductivity value
0 × 000A- Position of decimal point for above value (20.00 mA)
0 × 000B- Measurement unit of above value (20.00 mA)
Decimal Point Response:
0 × 0000 (Reading × 1)
0 × 0001 (Reading × 0.1)
0 × 0002 (Reading × 0.01)
0 × 0003 (Reading × 0.001)
Measurement Unit Response:
0 × 0006: mS/cm
0 × 0007: µ S/cm
0 × 0008: ppt
0 × 0009: ppm
For Example (Hexadecimal):
PC send:
02 03 00 00 00 02 C4 38
(Read the conductivity)
Response:
02 03 02 02 BC FC 95
(700)
PC send:
02 03 00 01 00 02 95 F8
(Read the decimal point)
Response:
02 03 02 00 01 3D 84
(Reading × 0.1)
PC send:
02 03 00 02 00 02 65 F8
(Read the measurement unit)
Response:
02 03 02 00 07 DB 86
(µ S/cm)
The result will show 70.0 µ S/cm (700 × 0.1 µ S/cm)
Electrode Maintenance
In order to maintain an accurate measurement, the electrode needs
cleaning and regular maintenance.
•
Remove the conductivity electrode from service and rinse the
platinum sensor on the bottom of the electrode.
•
Do not touch the platinum black coating on the sensor surface
and always keep it clean.
•
If there is a build-up of solids inside the sensor, remove carefully,
then recalibrate the electrode.
•
If you do not use the electrode for long periods, wipe clean with
a lint-free tissue and store the electrode in a dry and cool area.
•
If your electrode is model IE-50HT, store the electrode with tap
water. This sensor needs to be kept wet always.
Appendix
Troubleshooting
Fault
Cause and Corrective Action
Electrode dried out.
Soak the conductivity electrode in tap water for
about 10 minutes.
Measurement exceeded the maximum range.
Check the electrode and sample.
Drifting erratic
readings
Check whether electrode is contaminated, clogged
or broken.
Setting value does not match calibration solution.
Reset the calibration value or check the calibration
solution.
Electrode is broken.
Replace the conductivity electrode.
Preparation of Conductivity Standard Solutions
1. Place the analytical grade potassium chloride (KCl) in a beaker
and dry in an oven for about 3 hours at 105° C (221° F), then cool
to room temperature.
2. Add the reagent to a 1 liter volumetric flask according to the
instructions in table below.
Conductivity Standard
Reagent
Weight
84 µ S/cm
KCl
42.35 mg
1413 µ S/cm
KCl
745.5 mg
12.88 mS/cm
KCl
7.45 g
111.8 mS/cm
KCl
74.5 g
3. Fill the distilled water to the mark, mix the solution until the
reagent is completely dissolved.
Calculating the Temperature Coefficient
1. Do not connect the temperature probe to the meter.
2. Press and hold the
° C
key to enter the temperature setting.
3. Press the
/
key to set the temperature to 25° C and press
the
Enter
key to confirm.
4. Place the conductivity electrode into the sample solution, record
the temperature value T
A
and conductivity value C
TA
.
5. Condition the sample solution and electrode to a temperature T
B
that is about 5 to 10° C different from T
A
. Record the conductivity
value C
TB
.
6. Calculate the temperature coefficient using the formula below.
Platinum
black coating
