Parr Instrument 6772 - Manual (Page 36)

6772
Calorimetric Thermometer Instruction Manual
5-10
Thermochemical Corrections Menu
The Thermochemical Corrections Menu
permits three types of fixed corrections for
standardization (instrument calibration) runs,
and the same three types for determination
(test) runs. Pressing the LEFT side of each
key toggles the correction ON or OFF.
Press the RIGHT side of each key to access
the specific numeric dialog box where that
fixed value can be set. Each value entered
for these fixed corrections is used in all
preliminary reports.
When any fixed correction is set to ON, the
specified value will be used in the final reports, and the 6772 will not prompt for actual
corrections to be entered. (If all corrections are fixed, then preliminary and final reports will
be identical).
When any fixed correction is set to OFF, during the data entry reporting steps the user will be
prompted to enter an appropriate desired value which will be used in the final report.
Standardization Correction
Fixed Fuse Correction:
Press this key on the LEFT side to toggle ON or OFF the fixed fuse correction for
standardization runs. Press it on the RIGHT side to access the Fixed Fuse numeric dialog
box on which the value can be set. An appropriate fixed fuse value is 15 calories.
Acid Correction:
Displays both the ON/OFF of the fixed acid corrections for standardization runs and the value
of the correction. This key toggles the options for treatment of the acid correction and
accesses a submenu on which the value is set. An appropriate fixed HNO3 value is 10
calories when one-gram benzoic acid pellets are used to calibrate the instrument.
Options for the Acid Correction:
Fixed HNO
3
Calculated HNO
3
Entered Total
Entered HNO
3
Fixed Total
These options are discussed further in Section 6 - Calculations.
Fixed Sulfur Correction:
Press this key on the LEFT side to toggle ON or OFF the fixed sulfur correction for
standardization runs. Press it on the RIGHT side to access the Fixed Sulfur numeric
dialog box on which the value can be set. When benzoic acid is used as the calibrant,
a fixed sulfur value of zero should be used.