Parr Instrument 6200 User Manual

Page 27

6200

Calorimeter Operating Instruction Manual

Operating the

Calorimeter

All operations required to standardize

the 6200 Calorimeter, or test an unknown
sample, should proceed step-wise in the
following manner:

1. Turn on the calorimeter and activate

the pump and heater using
Calorimeter Operations. Allow at
least 20 minutes for the calorimeter
to warm up and the jacket
temperature to stabilize. Once the
jacket temperature comes within
0.5°C of 30°C and stays there for
approximately 10 minutes, the
calorimeter is ready to begin testing.
The bomb parts should be wetted
and then dried in the manner used at
the conclusion of a test. This serves
to wet all sealing parts as well as
leaving the bomb with the same
amount of residual water which will
exist in all subsequent testing.

2. Prepare the sample weighing the

material to 0.1 mg and charge the
oxygen bomb as described in the
section entitled, Operating the Filling
Connection. Using an additional
bomb and bucket can increase the
throughput of the 6200 Calorimeter.
With this arrangement, the
calorimeter can operate almost
continuously since the operator will
be able to empty a bomb and
recharge it while a run is in progress.
A bomb and bucket for the next run
will be ready to go into the
calorimeter as soon as it is opened.

Each bomb and bucket
combination will have to be
standardized separately and the
proper energy equivalent for each
set must be used when calculating
the heat of combustion.

3. Fill the calorimeter bucket by first

taring the dry bucket on a solution or
trip balance; then add 2000 (+/- 0.5)
grams of water. Distilled water is
preferred, but demineralized or tap
water containing less than 250 ppm
of dissolved solids is satisfactory.
The bucket water temperature
should be approximately 3 to 5 °C
below the jacket temperature. It is
not necessary to use exactly 2000
grams, but the amount selected
must be duplicated within +/- 0.5
gram for each run. Instead of
weighing the bucket, it can be filled
from an automatic pipet, or from any
other volumetric device if the
repeatability of the filling system is
within +/- 0.5 ml.

To speed and simplify the bucket
filling process, and to conserve
water and energy, Parr offers a
closed circuit Water Handling
System (No. 6510). This provides a
water supply, cooled to the starting
temperature and held in an
automatic pipet ready for delivery in
the exact amount needed to fill the
bucket. Instructions for this
automatic system are given in
Operating Instruction No. 454M.

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