2 ph – Xylem HandyLab 680 User Manual
Page 106

What to do if...
HandyLab 680
106
ba77041e01
03/2014
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