Siemens SIMATIC NET Operating Instructions Manual page 42

Connection
Note
Power supply, input and output cabling (I/O cabling) must meet the wiring standards for
Class I, Div. 2 - article 501 - 10B National Electric Code.
EXPLOSION HAZARD
DO NOT OPEN WHEN ENERGIZED.
Safety notices for use according to ATEX and IECEx
If you use the device under ATEX or IECEx conditions you must also keep to the following
safety notices in addition to the general safety notices for protection against explosion:
EXPLOSION HAZARD
DO NOT CONNECT OR DISCONNECT EQUIPMENT WHEN A FLAMMABLE OR
COMBUSTIBLE ATMOSPHERE IS PRESENT.
Take measures to prevent transient voltage surges of more than 40% of the rated voltage.
This is the case if you only operate devices with SELV (safety extra-low voltage).
If the cable or conduit entry point exceeds 70 °C or the branching point of conductors
exceeds 80 °C, special precautions must be taken. If the equipment is operated in an air
ambient in excess of 50 °C, only use cables with admitted maximum operating temperature
of at least 80 °C.
42
WARNING
WARNING
WARNING
WARNING
Operating Instructions, 01/2020, C79000-G8976-C270-06
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