palintest Photometer 7500 Operation Manual

Also see for Photometer 7100: Manual

palintest Photometer 7500 Operation Manual Manual pdf 31 page image

306.3 Blanking the Photometer 7500 BluetoothBlanking the photometer is a key first step in photometricanalysis, effectively removing the potential entrained samplecolour and minor amounts of turbidity from calculation ofanalytical results.To blank the photometer, prepare a Blank cuvette usinguntreated sample i.e. sample that has not been reacted withany reagents. If the sample is to be diluted or physicallytreated (filtered for example) before analysis, use the samedilution/treatment for the Blank cuvette.When accessing the test method the Photometer 7500Bluetooth will request the user to Insert BlankInsert the Blank cuvette and press OKThe Photometer 7500 Bluetooth will determine theabsorbance due to the sample colour at all wavelengthssimultaneously and store in temporary memory for use inanalysis.Upon successful blanking the Photometer 7500 Bluetooth willautomatically move to the Insert sample stage of theanalytical method.If the sample is too highly coloured to support effectiveblanking and subsequent analysis the error message “Error 9is caused by the blank cuvette being too dark. Check thecorrect is being used”Ensure the blank cuvette is being used, not the sample plusreagent cuvette. Sample colour can be reduced by dilutionwith clean water; the dilution selected should take account ofthe expected concentration of parameter under test.Blank results are stored in the temporary memory of thePhotometer 7500 Bluetooth and will be used for allsubsequent tests until: The instrument is powered down (temporary memory