palintest Macro 900 Operation Manual

Contents

palintest Macro 900 Operation Manual Manual pdf 52 page image

Macro 900 Operation Manual V3© 2013 Palintest Ltd. www.palintest.com Page 52 of 14715. Optional Optical Probes Calibration and MaintenanceThe MAP 2000/2100 is constructed with an aluminium sleeve surrounding thedelicate sensing probes. The Sleeve can be easily removed by unscrewing toallow cleaning of the individual electrodes, however, the Probe sleeve formsan integral, working part of the Probe’s measurement system, andMUST be fitted for correct operation.All Palintest Optical Probes are incredibly sensitive. For example, the Turbidityelectrode is capable of measuring between 0 and 3000NTU with an internalresolution of greater than 0.1NTU. This means that the electrode is able todetect changes in turbidity that are less than 0.003% of the full range! Theother Optical Probes have a similar level of sensitivity.It follows, therefore, that in order to provide stable, repeatable readings, theenvironment in which the measurements are made must be completely stableand repeatable.For this reason, the MAP2000/2100 is constructedwith a matt black aluminiumsleeve and end cap thatenclose the sensingelectrodes and provide aclosed, constant condition,non-reflective measurementchamber.This is essential for thecorrect calibration andoperation of all types ofOptical Probes.A diagram of the MAP2000/2100’s measurementchamber is shown here.In order to obtain consistent results, the measurement chambercreated within the Macro Accessory Probe must remain physicallyconstant during both calibration and measurement.If the optical electrode is calibrated under one set of conditions then used tomeasure under another set of conditions, the readings will naturally beerroneous, especially at low concentrations.A perfect example of this is calibrating with the end cap removed thenmeasuring with the end cap fitted (or vice-versa). By changing the physicalcharacteristics of the measurement chamber, you also change the calibrationand response of the electrode.