KERN & SOHN MLS 50-3C - Manual (Page 74)

74 MLS_C-BA-e-1330
11.7 Drying temperature
Bear in mind the following factors when setting the drying temperature:
Surface of the sample:
Compared with powdery or grainy samples, liquid and spreadable samples have a
smaller surface for the transmission of heat energy.
The use of a glass fibre filter improves the heat application.
Colour of sample:
Light-coloured samples reflect more heat radiation than dark ones and therefore
require a higher drying temperature.
Availability of volatile substances:
The better and faster the water or other volatile substances can be disposed, the
lower a drying temperature is required. If water is difficult to get to (e. g. in
synthetics), it has to be calcined at high temperatures (the higher the temperature,
the higher the water vapour pressure).
Results equivalent to other moisture analysing methods (e. g. drying chamber) can
be achieved by experimentally optimising the setting parameters such as
temperature, heating level and shutoff criteria.
11.7.1 Drying temperatures above 160 °C (MLS 50-3HA250N only)
For measurements within a temperature range from 161°C – 250°C, the heating
period is limited to 1 hour for up to 161°C and 20 minutes at 250°C.
The maximum temperature of 250°C is kept for 20 minutes and afterwards lowered
automatically within 20 minutes to 160°C (drying process is not interrupted).