Thermo Fisher Scientific Ion Selective Electrodes Lead - Manual (Page 21)

Instruction Manual Lead Electrode
19
TROUBLESHOOTING HINTS
Symptom Possible Causes
Next Step
Out of Range defective meter check meter with shorting strap
Reading (see meter instruction manual)
defective electrode check electrode operation
electrodes not unplug electrodes and reset
plugged in properly
reference electrode be sure reference electrode
not filled is filled
air bubble on membrane remove bubble by re-dipping electrode
electrodes not put electrodes in solution
in solution
Noisy or
defective meter check meter with shorting strap
Unstable Readings
(readings
air bubble on membrane remove bubble by re-dipping electrode
continuously
or rapidly changing) electrode exposed
soak electrode in lead standard
to interferences
defective electrode replace electrode
ISA not used use recommended ISA
meter or stirrer ground meter or stirrer
not grounded
Drift (reading
samples and standards allow solutions to come to room
slowly at different temperatures temperature before measurement
changing in one
direction)
complexing agents check section entitled
in sample
Precipitation and Complexation
incorrect reference use recommended
filling solution filling solution
membrane dirty polish membrane; use
or oxidized methanol-formal dehyde solution