User Manual
Table Of Contents
- 1 Overview
- 2 Safety
- 3 Commissioning
- 4 Operation
- 4.1 Switching on the meter
- 4.2 Login with a user name
- 4.3 General operating principles
- 4.4 Sensor-independent settings
- 4.5 Sensor info
- 4.6 Channel display
- 4.7 pH value
- 4.7.1 General information
- 4.7.2 Measuring the pH value
- 4.7.3 Settings for pH measurements
- 4.7.4 pH calibration
- 4.7.5 Calibration interval
- 4.7.6 Carrying out an automatic calibration (AutoCal)
- 4.7.7 Carrying out a manual calibration (ConCal)
- 4.7.8 Displaying calibration records
- 4.7.9 Continuous measurement control (CMC function)
- 4.7.10 QSC function (sensor quality control)
- 4.8 ORP voltage
- 4.9 Dissolved oxygen
- 4.10 Conductivity
- 4.11 Data storage
- 4.12 Transmitting data (USB interfaces)
- 4.12.1 Outputting current measurement data
- 4.12.2 Transmitting data (to a PC)
- 4.12.3 Connecting the PC / USB-B interface (USB Device)
- 4.12.4 Options for data transmission to a PC (USB-B interface)
- 4.12.5 Connecting the USB memory device / USB-A interface (USB Host)
- 4.12.6 Data transmission to a USB memory device (USB-A interface)
- 4.13 Reset
- 5 Maintenance, cleaning, disposal
- 6 What to do if...
- 7 Technical data
- 8 Lists
- 9 Appendix: Firmware update

Multi 3430 What to do if...
105
ba75865e11 02/2011
6.2 pH
Error message,
OFL, UFL
Error message,
Error
Cause Remedy
IDS pH sensor:
– Measured value outside the
measuring range
– Use suitable IDS pH sensor
– Air bubble in front of the junction – Remove air bubble
– Air in the junction – Extract air or moisten junc-
tion
– Cable broken – Exchange IDS pH sensor
– Gel electrolyte dried out – Exchange IDS pH sensor
Cause Remedy
IDS pH sensor:
– The values determined for zero
point and slope of the IDS pH
sensor are outside the allowed
limits.
– Recalibrate
– Junction contaminated – Clean junction
– IDS pH sensor broken – Exchange IDS pH sensor
– Buffer solutions:
– The used buffer solutions are not
suitable for the selected buffer
set
– Select a different buffer set
or
– Use different buffer solu-
tions
– Buffer solutions too old – Use only once.
Note the shelf life
– Buffer solutions depleted – Change solutions