Concentration Measure (Tds); Limits Of The Tds Measure - Hach POLYMETRON 9125 Operator's Manual

Transmitter 9125 – Conductivity / resistivity measurement

Concentration measure (TDS)

Limits of the TDS measure

Weight % ppm NaCl
0,0001 1
0,0003 3
0,001 10
0,003 30
0,01 100
0,03 300
0,1 1000
0,3 3000
1 10000
3
30000
5
50000
10 140000
100000
20 225000
200000
30
300000
40
400000
50
500000
75
750000
100 1000000
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The Total Dissolved Solid (TDS) measure is a
concentration measure in the limits of measure where,
for a part given, the concentration of the solution is
proportional to its conductivity.
The next board show for the mains solutions, the
relations existing
conductivity (in ppm).
The white part of the board show the limits where the
TDS display is possible.
The measure in concentration (TDS) is given by the
formula :
TDS = Cond x KTDS
The KTDS coefficient is calculated during the process
calibration of the device. It must be between 0.00 and
5.00. If it is not in this interval, an error message will
display during the calibration.
For different substances, the limits of the measure
where the concentration is proportional to the
conductivity is given by the white part of the next
board:
NaOH NH4OH NH3 HCl
2,2 6,2 4,1 6,6
6,5 8,3 8,3 12
21,4 61,1 17 27
64 182 31 49
210 603 58 84
617 1780 102 150
1990 5820 189 275
5690 16900 329 465
17600 53200 490 810 103000
48600 144000 790 1110 283000
78300 223000 958 1115 432000
358000 1115 1120 709000
414000 968 4251 850000
292000 725 732000
191000 460
150000
The unit of the conductivity is μs/cm.
between concentration
H2SO4 HNO2 HF SO2
11,7 8,8 6,8 10
50 61 20 30
116 85,6 67 99
340 251 199 290
1140 805 657 630
3390 2180 1950 1490
11100 6350 6380 2420
32200 15800 18900 5100
48500 60000 11700
141000 172000 34700
237000 275000 62000
427000 498000 118000
709000 763000 232300
828000 861000 390000
770000 820000
620000 717000
182000 340000
10000 50000
and
Acid
Acetic
6,4 4,2
18 7,4
54 15
150 30,6
450 63
1200 114
3600 209
7900 368
17200 640
32700 1120
42000 1230
61000 1530
1600
1405
1080
740
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