EMI RFI Filters are required in two situations, to prevent EMI from an Electronic Equipment Like A Dimmer, Thyristor Drive, SMPS or Switcher affecting other Modules in a System or Neighboring Equipment. The Second Situation is when a Sensitive Equipment Like a Medical Apparatus or Precision Measuring Instrument has to be Immune to any Noise from outside, as it can affect performance.
Sometimes it is Accuracy that can get affected, but some electrical jolts can damage or desensitize fine sensors or positioning systems.
On the right you can see a Filter that i used to make long ago, This is connected in series with an Existing Mains Chord. It can also be Fixed in a Control Panel with a Clamp. One Y cap is Missing in this Piece. The Big one must be the X cap a higher Capacitance Value. The Y cap is Lower Value and withstands around 1kV, It is better if X cap is AC 440V.
- RadioFrequency Interference/ElectroMagnetic Interference
- eEngineer – Electrical Engineering, EMI/EMC, RFI
- EMI Shielding RF Shielding
- Dealing with Computer generated RFI/EMI
- WEMS Electronics – EMI Filters / RFI Filters
- Basic EMI / RFI Filter Configurations
- TDK – Electronic Components & Materials
Here is one type i encountered in many T&M Instruments along with TDK too. It was Schaffner – electromagnetic compatibility – International leader in electromagnetic compatibility (EMC) and power quality (PQ). EMC Filters, RFI Suppression Chokes, Feedthrough Components.
Schaffner – @SchaffnerEMC – EMC/EMI components, harmonic filters & magnetic components.