Siemens Siwarex U, Device Manual

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3BHARDWARE CONFIGURATION AND INSTALLATION
Only use shielded data lines. The shielding must be connected extensively to
ground on both sides of the data lines.
The shielding of the measuring lines must also be connected to ground at both ends.
The shielding should continue right up to the terminal connection. The unshielded
line ends are to be kept as short as possible. Lay the cable shielding directly under
SIWAREX U on the shield connection element. The connection between shield
rails and cabinet/housing must be low in impedance.
Only use metallic or metallized plug housing for shielded data lines.
Rule 4: Special EMC measures
Wire all inductivities which are controlled with quenching circuits.
Use interference suppressed fluorescent lighting or incandescent lamps for
illuminating cabinets or housings in the immediate vicinity of your controls.
Rule 5: Uniform reference potential
Create a uniform reference potential and ground all electrical equipment.
Lay sufficiently dimensioned potential equalization conductors when there are
potential differences between parts in your system or where these are anticipated.
For explosion applications, potential equalization is absolutely necessary.
4.3 Installation on the profile rail
When assembling the SIMATIC modules and SIWAREX U, the SIMATIC S7 set-up
guidelines must be observed.
SIWAREX U is installed in the following steps:
•
Check whether the SIMATIC bus connector is connected to the module left
of SIWAREX U.
•
Connect the SIMATIC bus connector for the following module group in the
SIWAREX if necessary.
•
Install the shield connection element under SIWAREX.
•
Mount SIWAREX U on its place.
•
Screw down SIWAREX U with the screw in the lower area of the module.
•
Label SIWAREX U in accordance with its labeling system.
SIWAREX U
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