Hanna Instruments HI 84184 - Manual (Page 16)

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• Reassemble reference electrode by gently pushing the inner assembly into the outer body,
sliding spring down cable, and screwing cap into place.
• Remove fill hole cover and o-ring or fill hole spout.
• Using the dropper pipette provided, add a few drops of HI 7075 filling solution to the
reference electrode, wetting the o-ring and rinsing out the fill solution chamber.
• Holding the body of the electrode depress the black cap with your thumb. This permits the
fill solution to drain out of the body. Verify if the electrode returns to its original position.
(You may need to gently assist for this to occur).
• Tighten the electrode cap onto the body and fill electrode body with HI 7075 filling solution
until fill solution volume is just below fill hole.
• Place sensor and reference electrode into electrode holder and connect the Cable Connectors
to the instrument.
Note: During measurement always operate reference electrode with the fill hole open.
CLEANING PROCEDURE
• Rinse the fluoride electrode with deionised water. Check to see if the small scratches have
been eliminated.
• Soak the fluoride electrode in a standard for one hour.
• Rinse with deionised water and blot dry.
REFERENCE ELECTRODE CLEANING
• Drain the old filling solution, rinse with an adequate HI 7075 solution, drain, then refill with
HI 7075 solution.
• Do not use an electrode if cristalised salts are visible inside the electrode. Drain electrode,
disassemble and rinse internal body with deionised water. Reassemble and refill with fresh
refill solution.
• The internal chamber of this electrode is gell filled. If the electrode has been left dry for long
periods of time the gell may be dehydrated and stable measurements may not be obtainable.
Disassemble electrode and soak internal assembly in HI 7075 filling solution. Verify the
ceramic is wetted by the fill solution. Warming the solution slightly (50 °C) before soaking
will hasten this process. Permit the electrode to cool completely while immersed in this
solution.
QUICK CHECK OF THE ELECTRODE SLOPE
• Connect the electrode and the reference electrode to the instrument.
• Press and hold down ESC, and HELP keys simultaneously and power on the meter. Wait
until the instrument enters in the reading check mode.
• Place 50 mL of deionized water into the beaker with a stir bar.
• Add 1 mL of HI 84184-1 Standard. Record the mV value when stable.
• Add an additional 10 mL of HI 84184-1 Standard to the solution. Wait for the reading to
stabilize and record the mV value.