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© AMETEK, Inc.
9 MEASURING
9.1 Magnetic stirrer
Stirring is required by most standard flashpoint tests. As such the magnetic stirrer should always be used. If
inhomogeneous, diluted or contaminated samples are be tested, use the stirring magnet which is provided with the
instrument’s accessories.
Before the samples are filled into cups place one magnet into each cup that is filled with sample.
Use only stirring magnets provided with the instrument’s accessories only.
9.2 Start measurement
Press START MEASUREMENT to start the measurement. Three strong arcs for automatic cleaning the electrodes
are initialized, and the sample cup is pressed onto the oven plate by the sample cup lift.
9.2.1 Checking the sample temperature
After a few seconds the sample temperature is checked and if it is higher than the initial temperature, the
measurement is interrupted, because no regular measurement can be carried out. Together with this check, arcs
are being produced to check for a possible flash point below the starting temperature. In case a flashpoint is
registered, the initial temperature Ti was set too high for this sample.
Pre-cooling of the sample can be performed by setting Ti-T in the measurement screen. The analyzer will then
actively cool the sample to a temperature below the initial temperature (Ti).
9.2.2 Check of sample and initial temperature
An equilibrium time is started to heat the sample close to 3°C (5°F) of the oven temperature. During the increase
of the sample temperature arcs are initiated each step of 5°C (9°F) to avoid over saturation of the vapor in case
the initial temperature was set too high for this sample. If the equilibrium time expires without reaching this
temperature, the measurement is interrupted.
9.2.3 Flash point test
After this checks the oven temperature is raised with the programmed heating rate.
When the sample has reached the starting temperature, the first ignition for a flash test is initiated and the
pressure increase is monitored. If it is below the threshold the measurement is continued.
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