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A YES/NO entry enables/disables the use of gelatine capsule temperature deduction.
Note that the 'GELATINE CAPSULE' enable setting is retained after each sample. If a sample without a
capsule is burned then the capsule compensation must be disabled (CMD=28, NO)
In the 'EASY SPIKE' method the Capsule Rise value (CMD=29) is deducted from the measured
temperature rise (Sample + Capsule) before the result is calculated.
The operation is very easy:
1. Enable the easy spike process (CMD=28)
2. Tare the empty capsule
3. Put the sample in to the capsule
4. Weigh the filled capsule and enter the weight as MASS
5. Perform the determination
14 CORRECTIONS
The corrections are applied because they should not appear in the final result or some value was added
during the combustion process.
14.1 COTTON CORRECTION
Some energy is added to the burning process as a result of:
Firing energy
Wire oxidation
Electronic heating
Cotton thread
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COTTON+WIRE CORR
This is the cotton and wire correction. The cotton has a definable energy and the electrical current
which heats the firing wire has a constant energy contents. Both these (and others which produce an
offset) are combined in this entry. The default value is 0.0593C. The entry is in CENTI GRADE. This
correction is ALWAYS applied: To samples and calibrations alike. If the cotton or firing wire are changed
then the value should be re-adjusted to suit.
The 'Cotton correction' is constant. It is therefore treated as temperature rise compensation. The cotton
correction is subtracted from the raw temperature rise to yield the NETT RISE.
14.2 SULPHUR CORRECTION
If the sample contains sulphur then energy is released during the formation of SO2 from oxygen and
sulphur. This energy is deducted from the nett CV. The sulphur content of the sample must be measured
before and the CV (KJ/g) of SO2 formation must be entered:
DDS CALORIMETERS OPERATIONS MANUAL V1.1
1
2022
Digital Data Systems (Pty) Ltd.
CAL3K Advanced Bomb Calorimeters
www.ddscalorimeters.com
Website:
www.ddscalorimeters.com
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