Thermo Fisher Scientific Ion Selective Electrodes Fluoride - Manual (Page 20)

Instruction Manual Fluoride Electrode
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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 plugged unplug electrodes and reset
in properly
reference electrode be sure reference electrode is
not filled filled
air bubble on membrane remove bubble by re-dipping
electrode
Noisy or Unstable
defective meter check meter with shorting strap
Readings (readings
continuously or
air bubble on membrane remove bubble by re-dipping
rapidly changing) electrode
TISAB not used use recommended TISAB
meter or stirrer ground meter or stirrer
not grounded
defective electrode replace electrode
electrode exposed soak electrode in fluoride
to interference standard with added TISAB
Drift (reading
samples and standards allow solutions to come to room
slowly changing at different temperatures temperature before measurement
in one direction)
electrode exposed to check section entitled
complexing agents Complexation
incorrect reference use recommended
filling solution filling solution
Low Slope or
standards contaminated prepare fresh standards
No Slope or incorrectly made
TISAB not used use recommended TISAB
standard used as TISAB use TISAB
electrode exposed check section entitled