5.6
Temperature compensation
The temperature coefficient specifies the
change in conductivity per degree of
temperature change. It depends on the
chemical composition of the medium and
the temperature itself.
In order to compensate for this dependence,
four different compensation types can be
selected in the Liquisys M:
Linear compensation
The change between two temperature points
is considered to be constant, i.e.
α
= const.
The
α
value can be edited for the linear
compensation type. The reference temperature
is 25 °C.
NaCl compensation
The NaCl compensation (according to
IEC 746) is based on a fixed nonlinear curve
that defines the relationship between the
temperature coefficient and the temperature.
This curve is used for lower concentrations.
Ultrapure water compensation
Just like the NaCl compensation, the ultrapure
water compensation is based on a nonlinear
curve stored in the instrument.
This curve is split up into NaCl solution and
ultrapure water components. These are
calculated separately but then used together
to determine the overall relationship.
Conductivity
(uncompensated)
1
α
Temperature T
KOMPLIN.CDR
Fig. 5.12
Linear temperature
compensation
Temperature [°C]
2.7
2.5
2.3
2.1
Te
mp
er
at
ur
e
c
o
e
ffi
c
ie
n
t
α
[%/
K
]
NACLKOMP.CDR
0
96
144
48
Fig. 5.13
NaCl compensation
Instrument configuration
Liquisys M CLM 223 / 253
42
Hauser
