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P4 — Clear stored data (No—Yes)
1. Press , “No” flashes, press to select
No
or
Yes
, press
to confirm;
2. Press to enter P5 or press to return to measurement mode.
P5 — Restore to factory default setting (No—Yes)
1. Press , “No” flashes, press to select
No
to
Yes
, press
to confirm; The meter returns to measurement mode.
2. If not selecting “Yes”, press to return to measurement mode.
5.7
pH Electrode’s Maintenance
5.7.1 Daily maintenance
The soaking solution contained in the supplied protective bottle is used to maintain hydration of the glass bulb
and liquid junction. Loosen the cap, take out the electrode and rinse in distilled or water before taking a
measurement. Insert the electrode and tighten the cap after measurements to prevent the solution from leaking.
If the storage solution is cloudy or moldy, replace the 3M KCL solution. Oakton electrode storage solution
00653-04.
* The electrode should
NOT
be soaked and stored in
purified or distilled
water, protein solution, acid fluoride
solution, or organic lipids. Distilled water or purified water is only recommended for rinsing electrodes.
5.7.2 Calibration buffer solution
For calibration accuracy, the pH of the standard buffer solution must be reliable. The buffer solution should be
refreshed often, especially after heavy use. We recommend the Oakton buffer assortment pack 05942-10
which contains 500 mL of pH 4.01, 7.00 and 10.00 pH buffers.The Oakton solution pack 05942-15 includes
the three buffers as well as electrode storage and cleaning solutions
5.7.3 Protect glass bulb
The sensitive glass bulb at the front of the combination electrode should not come in contact with hard surfaces.
Scratches or cracks on the electrode will cause inaccurate readings. Before and after each measurement, the
electrode should be rinsed with distilled water or purified water. If a sample sticks to the electrode or it’s
contaminated, the electrode should be thoroughly cleaned using a soft brush with soap water and then rinsed
with distilled water. After that, soak it in the KCL solution again for at least 6 hours.
5.7.4 Renew glass bulb
Electrodes that have been used over a long period of time will become aged. Submerge the electrode in
0.1mol/L hydrochloric acid for 24 hours, then rinse the electrode in distilled water, then submerge it in KCL
storage solution 00653-04 for 24 hours.
The method to prepare 0.1mol/L hydrochloric acid: dilute 9mL hydrochloric acid in distilled water to 1000mL.
