Five Basic Rules For Guaranteeing Emc - Siemens SIWAREX FTA Device Manual

Hardware Planning and Assembly
Capacitive coupling
Inductive coupling
Radiation coupling
4.3.5

Five Basic Rules for Guaranteeing EMC

If you follow these five basic rules, EMC can be guaranteed in most cases!
Rule 1: Large conductive grounding surface connections
Ensure that while installing the automation devices, a well-made ground
connection is made between the inactive metal components (see following
section).
Connect all inactive metal components and low-impedance components with
ground (broad cross-section).
Use screw connections on painted or anodised metal surfaces either with special
contact washers or remove the insulated protective surface in the contact areas.
Do not use aluminium if at all possible for ground connections. Aluminium oxidises
easily and is therefore less suitable for grounding connections.
Find a central location for connections between the grounding point and the ground
wiring system.
Rule 2: Proper and organised wiring
Separate the cabling into groups (high-voltage lines, power supply lines, signal
lines, ground wiring, data lines, etc.).
Run the high-voltage lines and ground wiring or data cables in separate channels
or bundles.
Run measurement lines as close to grounding surfaces as possible (e.g. support
beams, metal rails, cabinet panels).
Rule 3: Fasten cable shielding
Ensure that the cable shielding is connected properly.
Use shielded data wiring only. The shielding must be fastened to ground using
a large surface area on both ends.
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SIWAREX FTA