Measuring; General Information - wtw Cond 1970i Operating Manual

Operation
Preparatory activities
Temperature
compensation and
reference temperature
16
4.2

Measuring

4.2.1 General information

You can measure the following variables:
Conductivity
Salinity
Total dissolved solids (TDS)
The measuring instrument is supplied with the following functions:
AutoRange (automatic switchover of the measurement range). If a
measuring range is exceeded, AutoRange causes the measuring in-
strument to change automatically to the next higher measuring
range and back again. Therefore, the instrument always measures
in the measuring range with the highest possible resolution. The
function can be switched off.
The AutoRead function (drift control) for checking the stability of the
measurement signal. This ensures the reproducibility of the measur-
ing signal. For details of how to switch the AutoRead function on/off,
see page 20.
Perform the following preparatory activities when you want to measure:
1 Connect a conductivity measuring cell to the measuring instru-
ment.
2 Calibrate or check the measuring instrument with the measur-
ing cell. How to calibrate is described in section 4.3.
3 Select the measuring mode with <M>.
Warning
When connecting an earthed PC/printer, measurements cannot be per-
formed in earthed media as incorrect values would result. The RS232
interface is not galvanically isolated.
The calculation of the temperature compensation is based on the pre-
set reference temperature, 20 °C or 25 °C. For more detailed informa-
tion concerning the temperature compensation, see section 4.4 on
Tref page 28.
Cond 1970i
ba75692e02 07/2009