User Manual

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Inorganic metal oxide

Dilute acid less than 1mol/L

Organic lipid

Dilute detergent (weak alkaline)

Resin macromolecule

Dilute alcohol, acetone, ether

Proteinic haematocyte sediment

Acidic enzymatic solution (saccharated yeast tablets)

Paints

Dilute bleacher, peroxide

Notes:

1) The instruments will NOT give accurate and stable pH readings when measuring distilled or

deionized water. This because distilled and deionized water do not have enough ions present

for the electrode to function properly. To measure distilled or deionized water’s pH, users

need to use a specialized electrode. Contact us for more details.

2) The electrode housing is polycarbonate. When using cleaning solutions, take cautions on

carbon tetrachloride, trichlorethylene, tetrahydrofuran, acetone, etc., which will dissolve the

housing and invalidate the electrode.

5 mV MEASUREMENT

ORP measurement

Press key, and switch the meter to mV measurement mode. Connect ORP electrode (the 301Pt-S 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.

Notes on ORP measurement

5.2.1 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-6 is the data of standard ORP solution for 222 mV.

Table-6

°C

242

235

227

222

215

209

205

201

5.2.2 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