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17. Instrument Calibration
The
MP-800D
is factory calibrated to the specifications shown on the certificate supplied with the
instrument. To ensure that the instrument is continuing to operate within specification, periodic checks
on the accuracy of the temperature readings are recommended. If the accuracy of the instrument is
found to deviate from the specification or if it is a requirement of your local quality policy, the user
calibration procedure can be used to recalibrate the displayed temperature on the instrument.
The main menu screen displays the date on which a previous user calibration was performed and the
‘Notifications’ menu in ‘Settings’ will enable an alert to be set up as a reminder for calibration and can
be set to Never (default), Weekly, Monthly, Bi-annually or Annually. If no previous user calibration has
been performed, the main screen will display ‘Factory calibration’.
It is recommended that the calibration procedure is performed using suitable certified melting point
standards which bracket the expected range of your test samples. This will ensure the highest level of
confidence is maintained in the results generated with the instrument. A list of commonly used
melting point standards and nominal melting points is given below.
Name
Nominal Melting point*
Azobenzene
69
Vanillin
83
Benzil
96
Acetanilide
116
Phenacetin
136
Benzanilide
165
Sulfanilamide
166
Sulfapyridine
193
Dicyanodiamide
210
Saccharin
230
Caffeine
237
Phenolphthalein
263
*Note:
Confirm the certified melting point and melting point range with the certificate supplied with
the standard.
17.1 Calibration procedure
Before the calibration is carried out it is necessary to perform melting point determinations with up to
three certified melting point standards.
❖
Prepare the melting point standards following the guidelines given in section 11.1. For the most
accurate results, prepare three capillaries for each standard.
❖
Create a new measurement for each standard and run a melting point determination. Save
the results.
❖
From the main menu screen, touch the Calibration card to open the calibration summary screen.
