Ph Value / Orp Voltage; General Information - wtw Multi 340i Operating Manual

Operation
Preparatory activities
16
4.2

pH value / ORP voltage

4.2.1 General information

Perform the following preparatory activities when you want to measure:
1 Connect the pH electrode to the measuring instrument.
If necessary, press the <M> key repeatedly until the status dis-
play pH (pH measurement) or U (measurement of the ORP
voltage) appears.
2 Adjust the temperature of the buffer solutions or test solutions,
or measure the current temperature, if you measure without a
temperature sensor.
3 Calibrate or check the measuring instrument with the elec-
trode.
4 Using < > < >, toggle between the pH or mV measuring
modes.
Note
Incorrect calibration of pH electrodes leads to incorrect measured val-
ues. Calibrate regularly before measuring. You can only connect elec-
trodes of the NTC30 type or without temperature sensor.
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.
Multi 340i