Siemens SIMATIC NET SCALANCE W720, Operating Instructions Manual

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Connection
6.1 Safety when connecting up
SCALANCE W760 / W720
40
Operating Instructions, 03/2022, C79000-G8976-C322-13
WARNING
Lack of equipotential bonding
If there is no equipotential bonding in hazardous areas, there is a risk of explosion due
to equalizing current or ignition sparks.
•
Ensure that equipotential bonding is available for the device.
WARNING
Unprotected cable ends
There is a risk of explosion due to unprotected cable ends in hazardous areas.
•
Protect unused cable ends according to IEC/EN 60079-14.
WARNING
Improper installation of shielded cables
There is a risk of explosion due to equalizing currents between the hazardous area and
the non-hazardous area.
•
Ground shielded cables that cross hazardous areas at one end only.
• Lay a potential equalization conductor when grounding at both ends.
WARNING
Insufficient isolation of intrinsically safe and non-intrinsically safe circuits
Risk of explosion in hazardous areas
•
When connecting intrinsically safe and non-intrinsically safe circuits, ensure that the
galvanic isolation is performed properly in compliance with local regulations (e.g. IEC
60079-14).
• Observe the device approvals applicable for your country.
Notes for use in hazardous locations according to ATEX, IECEx, UKEX and CCC Ex
If you use the device under ATEX, IECEx, UKEX or CCC Ex conditions you must also keep
to the following safety instructions in addition to the general safety instructions for
protection against explosion:
WARNING
Transient overvoltages
Take measures to prevent transient overvoltages of more than 40% of the rated voltage
(or more than 119 V). This is the case if you only operate devices with SELV (safety
extra-low voltage).