Thermo Products REDOX/ORP 9678BNWP - Manual (Page 10)

 Redox/ORP Electrode User Guide
Measurement Techniques
• Always use fresh ORP standard for calibration.
• If the electrode is refillable, remove the filling hole cover
during measurements to ensure a uniform flow of filling
solution.
• Between measurements, thoroughly rinse the electrode
with distilled water. Gently shake the electrode after rinsing
to prevent solution carryover and then blot the electrode
dry with a lint-free tissue.
• Stir all standards and samples at a uniform rate.
• Place a piece of insulating material, such as Styrofoam or
cardboard, between the magnetic stirrer and beaker to
prevent measurement errors from the transfer of heat to
the sample.
• Allow all standards and samples to come to room
temperature for precise measurements.
• If the electrode is used in dirty or viscous samples or the
electrode response becomes sluggish, empty the electrode
completely and hold the junction under running water.
Empty any water from the electrode and refill it with fresh
electrode filling solution.
• If a Sure-Flow electrode is used in dirty or viscous samples
or the electrode response becomes sluggish, empty the
electrode completely and hold the junction open under
running water. Empty any water from the electrode and
refill it with fresh electrode filling solution. Press down on
the electrode cap to let a few drops of the filling solution
flow out of the electrode and then replenish any lost
solution.
• Make sure the electrode filling solution is appropriate
for the sample. Use Cat. No. 900011 filling solution for
samples that have a total ionic strength greater than 0.2 M.
Use Cat. No. 900001 filling solution for samples that have a
total ionic strength less than 0.2 M.