9782 Series Two Cell Conductivity/Resistivity Analyzer/Controller Operator's Manual

Conductivity/Resistivity Analyzer/Controller
Appendix D - 2 9782 Series Conductivity/Resistivity Analyzer/Controller - Operator’s Manual 7/99
Example 1: To determine the check resistor value needed to simulate conductivity measurement
of 10 µS, use cell constant 0.1 and perform the following calculation:
10 k ohms = (0.1) x (1,000,000)
10
Example 2: To determine the check resistor value needed to simulate resistivity measurement of
10 M ohms, use cell constant 0.01 and perform the following calculation:
100 K ohms = (0.01) x (10,000,000)
Concentration values
If a wide range model is used for concentration measurement, obtain the appropriate check
resistance value from the table below.
Data for Concentration Range Measurements
Material/Weight % Concentration Simulation Resistance (ohms) @ 25º C
Cell Constant
10 25 50
Hydrochloric Acid (HCl)
0
1
4
∞
242.5
68.9
∞
485.0
137.7
Sulfuric Acid (H2SO4)
0
1
4
∞
215.5
56.0
∞
538.7
140.0
∞
1077.4
280.0
Sodium Chloride (NaCl)
0
1
4
∞
574.1
195.2
∞
1435.1
398.0
∞
2870.3
796.1
Sodium Hydroxide (NaOH)
0
1
4
∞
189.2
54.0
∞
473.0
135.1
∞
946.1
270.1