Xylem MULTI 1970I PORTABLE MULTIPARAMETER METERS - Manual (Page 38)

Operation Multi 1970i
36
4.5 Conductivity
4.5.1 General information
Note
Conductivity measurements with the Multi 1970i can only be carried out
using the TetraCon 325 measuring cell.
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 measuring instrument is supplied with the following functions:
z 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.
z 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 39.
Preparatory activities Perform the following preparatory activities when you want to measure:
Temperature sensor The TetraCon 325 conductivity measuring cell has a temperature sen-
sor integrated in it. The temperature sensor is shown on the display by
TP.
1 Connect a conductivity measuring cell to the measuring instru-
ment. If the conductivity measuring cell is connected to the ac-
tive REL socket, press the <M> key repeatedly (if necessary)
until the status display
appears. If the conductivity measur-
ing cell is connected to the inactive REL socket, press the <M>
key for 2 s until the status display
appears.
2 Check the selected cell constant or calibrate the measuring in-
strument with the measuring cell (see below).
3 Check the selected cell constant (see below) or calibrate the
measuring instrument with the measuring cell (see
section 4.5.5 on page 40).
4 Using <
▲ > <▼>, toggle between the measuring modes, con-
ductivity ( in
µS/cm) or salinity (SAL).