HomeKnowledgeShielding & filtering

Guide · Measures

Reducing emissions — shielding, filters & grounding.

When a device radiates too much, four levers help — but only if they fit together. An overview of what really works.

Shielding

Conductive enclosures or foils block fields; absorber materials convert energy into heat. What matters is the 360° termination of shields — the classic “pigtail” (a single connecting wire) largely undoes the shielding effect.

Filtering

Line and signal filters, suppression capacitors and ferrite cores remove unwanted frequencies — effective only in the right place, close to the source or sink.

Cable routing & grounding

Separate signal and power lines, twist them (reduces the loop area) and implement a well-thought-out grounding and equipotential-bonding concept — often the biggest lever of all.

Interplay

The measures work together: a good grounding concept reduces emissions and increases immunity. That is why we look at the system as a whole.

Frequently asked questions

Shielding or filtering — which first?
Usually grounding and filtering at the source first, then shielding. Shielding does not replace a good grounding concept — it complements it.
Why isn't my shielding working?
Most common cause: poor termination (pigtail instead of 360°), slots in the shielding or open feed-throughs. We check this in the real setup.