IKA C 6000 global standards, Руководство по эксплуатации

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Complete combustion
To correctly determine the gross calorific value, it
is of fundamental importance that the sample un-
dergoes complete combustion. After each experi-
ment, the crucible and all solid residues must be
examined for any signs that combustion was not
complete.
In case of using substances tending to squirt it
is not possible to ensure complete combustion.
Substances with low flammability ( substances
with a high content of mineral matter and low-
calorific substances) will often undergo complete
combustion only with the aid of combustion cap-
sules or combustion bags (C 10/ C 12 see „Acces-
sories“). It is also possible to use liquid combustion
aids such as paraffin oil.
The combustion aids as well (for example the cot-
ton thread) must undergo complete combustion.
If unburned residues are left over, the experiment
must be repeated.
Adjustment (only IKA ® C 6000 global standards)
If the device is to be operated in adiabatic func-
tion, prior adjustment in the respective tempera-
ture range (22°C, 25°C or 30°C) is necessary.
Adjustment must be performed in the following cases:
•
When first commissioning the calorimeter and
when its place of installation has been changed.
•
If the measuring times for adiabatic measure-
ments are regularly in excess of 15-20 minutes.
•
If adiabatic measurements are frequently abort-
ed because the time limits for the pre trial or
main trial have been exceeded.
Procedure for adjustment:
•
Set the function depending on the desired
temperature range (Adjustment_22, Adjust-
ment_25, Adjustment_30).
•
Prepare for a formal single measurement. An
empty crucible is used. The fictitious value „1“
is entered for the weighted sample.
•
Start the measurement.
•
Adjustment starts automatically and is complet-
ed within approx. 1 hour. After the adjustment
has been successfully completed the adjustment
value appears as an increase in temperature in
the measurement record for the measurement
that was performed.
After successful completion of adjustment the de-
vice automatically changes the mode of operation
to the corresponding adiabatic mode.
Adjustment_22 Adiabatic_22
Adjustment_25 Adiabatic_25
Adjustment_30 Adiabatic_30