Appendix
Calculating the TDS Conversion Factor
The TDSscan20 tester allows setting the conversion factor according
to the type of sample. The factory default is 0.50. The following formula
describes the calculation method.
Factor =
Where:
Actual TDS = Value from the high purity water and precisely weighed
NaCl or KCL reagent
Actual Conductivity = The tester measured conductivity value
For example:
Dissolve 64 grams of the potassium chloride (KCl) reagent in 1 liter
distilled water. If measured conductivity is 100 mS/cm, then TDS factor
is 0.64.
Preparation of TDS Standard Solutions
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. Add the reagent to a 1 liter volumetric flask according
to the instructions in table below.
TDS Standard
Reagent
Weight
71.8 ppm
KCl
74.4 mg
744.7 ppm
KCl
745.5 mg
7447 ppm
KCl
7.45 g
Fill the distilled water to the mark, mix the solution until the reagent
is completely dissolved.
Optional Accessories
Order Code
Description
E-ECscan-C1-10K
Platinum conductivity cell, K=1
TDSCS-718
Standard solution 71.8 ppm, 480 ml
TDSCS-744
Standard solution 744 ppm, 480 ml
TDSCS-7447
Standard solution 7447 ppm, 480 ml
Tester Specifications
Model
TDSscan20
TDS
0 to 10.00, 100.0, 1000 ppm, max. 20.00 ppt
5
I
TDSscan20
Range
Resolution
0.01, 0.1, 1
Accuracy
±1% F.S.
Calibration Points
1 to 3 points
Temperature
Range
0 to 60°C (32 to 140°F)
Resolution
0.1°C (0.1°F)
Accuracy
±1°C (±1.8°F)
Calibration Point
1 point
Calibration Range
Reading ±10°C/°F
Other Specifications
Temperature Compensation
0 to 60°C (32 to 140°F), automatic
TDS Factor
0.1 to 1.0
Operating Temperature
0 to 50°C (32 to 122°F)
Storage Temperature
0 to 60°C (32 to 140°F)
Relative Humidity
< 80% (non-condensing)
IP Rating
IP54
Display
LCD, 21 × 21 mm (0.82 × 0.82 in.)
Power Requirements
2 × 1.5V AAA alkaline batteries
Auto-Off
8 minutes after last key pressed
Dimensions
185 (L) × 40 (Dia.) mm (7.28 × 1.57 in.)
Weight
100
g (3.5 oz.)
Actual TDS
Actual Conductivity @ 25°C
