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Resin macromolecule
Dilute alcohol, acetone, ether
Proteinic haematocyte sediment
Acidic enzymatic solution (saccharated yeast tablets)
Paints
Dilute bleacher, peroxide
6
mV measurement
6.1
ORP measurement
Press key, and switch the meter to mV measurement mode. Connect ORP electrode (the 301Pt-C
combination ORP electrode is sold separately) and dip it in sample solution, stir the solution briefly and allow
it to stay in the solution until icon appears and get the reading.
ORP means Oxidation Reduction Potential. The unit is mV.
6.2
Notes on ORP measurement
6.2.1 ORP measurement does not require calibration. When the user is not sure about ORP electrode quality
or measuring value, use ORP standard solution to test mV value and see whether ORP electrode or meter
works properly. Table-9 is the data of standard ORP solution for 222 mV.
Table-9
°C
10
15
20
25
30
35
38
40
mV
242
235
227
222
215
209
205
201
6.2.2 Clean and activate ORP electrode
After the electrode has been used over a long period of time, the platinum surface will get polluted which
causes inaccurate measurement and slow response. Please refer to the following methods to clean and
activate ORP electrode:
(a) For inorganic pollutant, submerge the electrode in 0.1mol/L dilute hydrochloric acid for 30 minutes, then
wash it in distilled water, then submerge it in the soaking solution for 6 hours.
(b) For organic or lipid pollutant, clean the platinum surface with detergent, then wash it in distilled water, then
submerge it in the soaking solution for 6 hours.
(c) For heavily polluted platinum surface on which there is oxidation film, polish the platinum surface with
toothpaste, then wash it in distilled water, then submerge it in the soaking solution for 6 hours.
7
Recommended pH Electrodes for Specific Applications
Application
Ideal Apera pH Electrodes to Use with
PH700 Meter
Regular water solutions
201T-F, LabSen 213
Beverage, beer, or wine analysis
LabSen 213
Cosmetics
LabSen 851-1, (MP500 temp. probe
