YOKOGAWA ISC450G User Manual

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IM 12D06D05-01E
A
APPENDICES
If it is more convenient, the user may make
solutionsfromSodiumChloride(NaClorcom-
mon table salt) with the help of the following
relationship table. This table is derived from the
IECnorm60746-3.
Table 11-3. NaCl values at 25 °C
Weight % mg/kg Conductivity
0.001 10 21.4 µS/cm
0.003 30 64.0 µS/cm
0.005 50 106 µS/cm
0.01 100 210 µS/cm
0.03 300 617 µS/cm
0.05 500 1.03 mS/cm
0.1 1000 1.99 mS/cm
0.3 3000 5.69 mS/cm
0.5 5000 9.48 mS/cm
1 10000 17.6 mS/cm
3 30000 48.6 mS/cm
5 50000 81.0 mS/cm
10 100000 140 mS/cm
APPENDIX 4
Measurement principle
Contrary to contact electrode conductivity,
theEXAISCSeriesanalysestheconductivity
with out any contact between electrodes and
proc ess fluid. The measurement is based on in-
ductive coupling of 2 ring trans form ers (Toroids)
by the liquid.
V
3
V
1
N
3
N
1
Drive coilReceive coil
The converter supplies a reference volt age at
ahighfrequencytothe“drivecoil”.Thecoreof
this coil is of a high permeability mag net ic ma-
terial, and a strong magnetic field is generated
in the toroid.
The liquid passes through the hole in the toroid
andcanbeconsideredasa“oneturn”second-
ary winding.
The magnetic field will induce a voltage in this
secondary winding. The induced cur rent in the
liquid winding is proportional to this volt age and
theconductanceoftheliquid“oneturnwinding”
isaccordingtoOhm’slaw.
The conductance (1/R) is proportional to the
specific conductivity and a constant factor that
is determined by the geometry of the sensor
(length divided by surface area of the hole in
the toroid) and the installation of the sensor.
Thereare2toroidsmountedinthe“doughnut”
shaped sensor. The liquid also flows through
the second toroid and therefore the liquid turn
can be considered as a primary wind ing of the
second ring transformer.
The current in the liquid will create a mag net ic
field in the second toroid. The induced volt age
being the result of this magnetic field can be
measured as an output.
Theoutputvoltageofthis“receivecoil”isthere-
fore proportional to the specific con duc tiv i ty of
the process liquid.

YOKOGAWA ISC450G Specifications

General

Brand	YOKOGAWA
Model	ISC450G
Category	Media Converter
Language	English