OptiMelt Automated Melting Point System - Stanford Research ...

66 Maintenance and Calibration Chapter 4Acceptability TestThe Acceptability Test will(1) check the accuracy of your OptiMelt’s temperature readings(2) determine if correction of the temperature offsets is required(3) calibrate the temperature offsets if necessary.During the Acceptability Test, the melting points of three Certified Reference Standards(CRSs) are measured and temperature offset corrections are calculated. If the magnitudeof any of the calculated temperature offset corrections exceeds the published accuracyspecifications of the instrument, the temperature offsets must be updated. To update thetemperature offsets, the calculated offset corrections are entered into the Calibrationmenu resulting in a fresh calibration.The step-by-step instructions listed in this section rely on the use of the SRS O100MPSCRS Kit (Appendix B) as the source of melting point standards. However, this procedureis also compatible with other Standards Kits obtained directly from local, national orinternational certification centers. The only compatibility requirement for a CRS kit isthat the melting point temperatures of its substances be fairly close to the nominalmelting points required for the three melting point determinations:CRS Rated or Nominal MP * (°C) Compatible MPs (°C )Low 83.0 75-95Middle 135.9 125-145High 237.0 225-250* O100MPS CRS Kit values.Table 3. Melting Points compatible with the Acceptability Test.The Acceptability Test also relies entirely on visual determination ofmelting points. A separate procedure must be followed to adjust theCamera Thresholds (Onset%, Single% and Clear%) to match the visualresults with the automated determinations for your specific samples.OptiMelt Automated Melting Point System