Parr Instrument 6755 - Manual (Page 8)

2
Quick Start
P a r r I n s t r u m e n t C o m p a n y 6
C
HAPTER
2
Quick Start
Before starting to use the calorimeter for the fi rst time, it is recommended that the user per-
form a dry run with the calorimeter completely assembled, but with no liquid in the Dewar and
no sample in the rotating cell. This will give the user an opportunity to become familiar with
the individual parts of the calorimeter and the manner in which they must be handled. The
calorimeter must be standardized prior to analyzing a sample.
See Chapter 3: Operation for more detail.
1. Allow at least 20 minutes for the calorimeter to warm up.
2. Turn on the stirrer motor switch on the 6755 calorimeter.
3. Prepare and weigh the sample to 0.0001g or 1 mL in the PTFE dish.
4. Fill the Dewar volumetrically or by weight.
5. Install the thermistor probe in the cover opening and press the bushing fi rmly into place to
anchor the probe in its proper position.
6. Lower the cover assembly with the cell and thermistor probe into the Dewar and set the
cover in place on the air can, then drop the drive belt over the pulleys, start the motor and
press the start key.
7. The pre-period will now start. When the reactants come to thermal equilibrium, the ther-
mometer will beep. Initiate the reaction by pressing downward on the push rod to drop the
sample out of the rotating cell.
8. During the reaction period, the enthalpy change will occur.
9. The calorimeter will again come to equilibrium during the post period and at the conclusion
of the test, the calorimeter will signal the user and produce a report.
10. Stop the calorimeter motor, raise the cover carefully and wipe any excess liquid from the
parts that were immersed in the Dewar. Remove the thermistor probe from the cover and
remove the sample dish from the end of the push rod; then remove the rod and release the
glass cell from the drive shaft.
11. Lift the Dewar out of the air can and empty it. Wash and dry all wetted parts carefully.
12. At the end of the testing period, press the key on the thermometer touch screen main
menu. Turn OFF the thermometer at the power switch when prompted.