Hanna Instruments HI 98240 Instruction Manual

Contents

Hanna Instruments HI 98240 Instruction Manual Manual pdf 17 page image

3332Put in the protective cap a few drops of HI 70300 storage solution or,in its absence, filling solution (HI 7071 for single junction or HI 7082for double junction electrodes). Follow the Preparation Procedureabove before taking measurements.Note: NEVER STORE THE ELECTRODE IN DISTILLED WATER OR DRY.PERIODIC MAINTENANCEInspect the electrode and the cable. The cable used for connection tothe meter must be intact and there must be no points of brokeninsulation on the cable or cracks on the electrode stem or bulb.Connectors must be perfectly clean and dry.If any scratches or cracks are present, replace the electrode.Rinse off any salt deposits with water.For refillable electrodesRefill it with fresh electrolyte (HI 7071 for single junction or HI 7082for double junction electrodes). Allow the electrode to stand upright for1 hour. Follow the Storage Procedure above.CLEANING PROCEDUREGeneral: soak in Hanna HI 7061 general cleaning solutionfor approximately 1 hour.Removal of films, dirt or deposits on the membrane/junction:- Protein soak in Hanna HI 7073 protein cleaning solutionfor 15 minutes- Inorganic soak in Hanna HI 7074 inorganic cleaningsolution for 15 minutes- Oil/grease Rinse with Hanna HI 7077 Oil & Fat cleaningsolutionIMPORTANT: After performing any of the cleaning procedures rinsethe electrode thoroughly with distilled water, drain and refill thereference chamber with fresh electrolyte (not necessary for gel filledelectrodes) and soak the electrode in HI 70300 storage solution for atleast 1 hour before taking any measurements.TROUBLESHOOTINGEvaluate the performance of your electrode based on the followingpossibilities:• Noise (readings fluctuate up and down) could be due to:- Clogged/Dirty Junction: refer to the Cleaning Procedure above.- Loss of shielding due to low electrolyte level (in refillableelectrodes only): refill with fresh HI 7071 for single junctionelectrodes, or HI 7082 for double junction electrodes.Note: To prevent damage to the electrode, remove it from the samplebefore turning the meter off.With the meter OFF, detach the electrode from the instrumentand immerse it in the storage solution.PREPARATIONRemove the protective cap.DO NOT BE ALARMED IF SALT DEPOSITS ARE PRESENT.This is normal with pH electrodes and they will disappear when rinsedwith water.During transport tiny bubbles of air may form inside the glass bulb.The electrode cannot function properly under these conditions. Thesebubbles can be removed by "shaking down" the electrode as youwould do with a glass thermometer.If the bulb and/or junction are dry, soak the electrode in HI 70300storage solution for at least one hour.For refillable electrodesIf the fill solution (electrolyte) is less than 1 cm (½") below the fillhole, add HI 7082 3.5M KCl electrolyte solution for double junction orHI 7071 3.5M KCl+AgCl electrolyte solution for single junctionelectrodes.For a faster response unscrew the fill hole screw during measurements.For AmpHel® electrodesIf the electrode does not respond to pH changes, the battery is rundown and the electrode should be replaced.MEASUREMENTRinse the electrode tip with distilled water.Immerse the tip (4 cm /1½") in the sample and stir gently forapproximately 30 seconds.For a faster response and to avoid cross contamination of the samples,rinse the electrode tip with a few drops of the solution to be tested,before taking measurements.STORAGETo minimize clogging and ensure a quick response time, the glassbulb and the junction should be kept always moist and not allowedto dry out.ELECTRODE CONDITIONINGAND MAINTENANCE