thuba TMS Manuel page 5

3. Requirements to be met by safety
temperature limiters
Safety temperature limiters have to meet re -
quirements over and above those of temperature
controllers, so that the temperature limits of the
given temperature class will not be exceeded. All
of the following conditions are checked during
the conformity assessment procedure specified
by the EU directive (details in Section 4 of the
Manual):
– Resetting with tool only
– Manual resetting
– Resetting under normal operating condi-
tions only
– Safeguarded temperature setting
– Independence from the automatic control-
system
– Protection against sensor failure (capillary
tube pressure relief device)
– Functional testing to EN 50495:2010
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