7 atex – JUMO 14597 safetyM STB/STW Ex - Safety Temperature Limiter and Safety Temperature Monitor Operating Manual User Manual
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7 ATEX
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Example:
A thermocouple is to be used in temperature class T4 (maximum temperature 135 °C, limit is to be reduced 5 K for safety);
T
s
Highest admissable temperature at the probe tip
T
s
= 130 °C – 0.9 °C
T
s
=
129.1 °C
The maximum temperature (measured or medium temperature) at the probe tip must therefore not exceed a value of 129.1 °C.
The following table presents a summary of the calculations for all temperature classes:
Table 18:
Media and ambient temperature for applications re-
quiring devices of category 2
Media and ambient temperature for applications re-
quiring devices of category 1
Sensor with PT100
Sensor with thermocouple
Sensor with PT100
Sensor with thermocouple
T1
439.1 °C
432.5 °C
349.1 °C
342.5 °C
T2
289.1 °C
282.5 °C
229.1 °C
222.5 °C
T3
194.1 °C
187.5 °C
154.1 °C
147.5 °C
T4
129.1 °C
122.5 °C
102.1 °C
95.5 °C
T5
94.1 °C
87.5 °C
74.1 °C
67.5 °C
T6
79.1 °C
72.5 °C
62.1 °C
55.5 °C