Hanna Instruments HI 98160 Instruction Manual

Also see for HI 98160: Instruction manual

Contents

8Setup can be used to view data regarding instrument status (e.g.battery charge) or to change the meter parameters (e.g. time).ï To enter this mode press the ALT andFNC keys when the meter is in measure-ment mode.ï The setup code "tC" will blink on thelower LCD and "SEt" will be displayed onthe upper one.ï Select the code of the desiredparameter using the arrow keys.ï Press the ALT and CFM keys to confirmthe code.Note: If the ALT and FNC keys are pressed before code confirmation,the meter will return to measurement mode.ï If the selected parameter is password protected, the lower LCD willdisplay "PAS" and the password must be entered to proceed.Otherwise, the current parameter value will be displayed.PASSWORD PROTECTIONSetting time, date and calibration alarm time-out are passwordprotected and the user will be asked to enter the password to changethese parameters. After code confirmation the upper LCD will display"0000".ï If password is set to 0000 (factory setting), just press the ALT andCFM keys to confirm.ï If password is set to a value different from 0000, enter thepassword with the up and down arrow keys and then press theALT and CFM keys to confirm.ï If password is incorrect the meter displays the "WRONG" indicationand asks for the password again.ï If password is correct, the meter provides access to all parameters.SETUP MODEFNCALTALTGLPFNCCFMRANGEFNC CFMAlkaline Error1.0 Mol L-1 Na+0.1 Mol L-1 Na+Sodium Ion Correction for the Glass at 20-25∞CConcentration pH Error13.0013.5014.0012.5013.0013.5014.000.100.140.200.100.180.290.40TEMPERATURE-RESISTANCE CORRELATION FORHANNA pH SENSITIVE GLASSThe resistance of glass electrodes partially depends on the temperature.The lower the temperature, the higher the resistance. It takes longer timefor the reading to stabilize if the resistance is higher. In addition, theresponse time will suffer to a greater degree at temperatures below 10∞C.Since the resistance of the pH electrode is in the range of 200 Mohm,the current across the membrane is in the pico-Ampere range. Largecurrents can disturb the calibration of the electrode for many hours.For these reasons high humidity environments, short circuits andstatic discharges are detrimental to a stable pH reading.The pH electrode's life also depends on the temperature. If constantlyused at high temperatures, the electrode life is drastically reduced.Typical Electrode LifeAmbient Temperature 1- 3 years90 ∞C Less than 4 months120∞C Less than 1 monthHigh concentrations of sodium ions interfere with readings in alkalinesolutions; the pH at which the interference starts to be significantdepends upon the composition of the glass. This interference is thealkaline error and causes the pH to be underestimated. Hanna'sglass formulations have the indicated characteristics.-20 -20-100 +10+20 +30+40 +50+60+70 +80+90 ° C-10-10Ω-10-10-10-10Ω2x1091x1092x1081x1082x1071x107-20 -10 0 +10 +20+30+40 +50 +60 +70+80 +90 ∞C25