Xylem WTW Multi 3430, Operating Manual

Page: 120 / 134

Multi 3430
What to do if...
120
ba75865e19 04/2015
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
– 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