IBP HDM99, Руководство пользователя

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Measurement 20
Basic information about the temperature
coefficient
The temperature coefficient in conductivity measurement is an important
subject that is frequently neglected. The conductivity of a solution changes
with the temperature. As the temperature rises, the conductivity of the
measurement solution increases also. In order to arrive at meaningful
measured values, the display value is compensated to 25°C. Expressed in
another way, the display is always converted to a solution temperature of
25°C. The temperature coefficient with which the display is compensated is
expressed in % / °C.
However, different solutions now unfortunately also have different
temperature coefficients. For the display to be precise, the measuring unit
must therefore be set to the temperature coefficient of the current solution.
The average temperature coefficient for dialysate is 2.07% / °C. A value of
1.97% / °C is frequently used for natural water.
To perfect the chaos, the different manufacturers of dialysis machines also
use different temperature coefficients in their machines.
Baxter
2,20 %/°C
Braun 2,00 %/°C
FMC 2,10 %/°C
Gambro 1,80 %/°C
Hospal 2,07 %/°C
Nikkiso
Bicarbonat 2,02 %/°C
Total conductivity 2,05 %/°C
This gives rise to the following recommendations:
1.
You have machines from one manufacturer only:
Use the temperature coefficient that the dialysis machine uses for
compensation
2.
You have machines from different manufacturers:
Use as a temperature coefficient a mean value.
2.07% / °C is recommended for this.