Siemens SENTRON, Manual

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Appendix
A.2 Operating conditions
216
Manual, 08/2017, L1V30368969104A-02
A.2 Operating conditions
A.2.1 Temperature
● At a temperature of -20 °C to +40 °C without derating
● At temperatures from - 20 °C to +70 °C, the derating correction factor K
t
must be factored
in
K
t
– correction factor
Temperature
0.9 40 °C to 50 °C
0.8 50 °C to 60 °C
0.7 60 °C to 70 °C
The simplified method of calculating the derating is used here:
l
thu
≤ I
th
x K
f
In a few cases, specific requirements demand precise derating calculations. Contact
Siemens for this.
A.2.2 Humidity
● At 80 % air humidity and 55 °C, condensation does not take place
● At 95 % air humidity and 40 °C, condensation does not take place
A.2.3 Altitude conditions
● Up to 2000 m no derating
● For higher altitudes, the following derating correction factor must be factored in
K
a
– correction factor 2000 m < A ≤ 3000 m 3000 m < A ≤ 4000 m
U
e
0.95 0.8
I
e
0.85 0.85