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EMI RFI Mains Power Filters

EMI RFI Noise 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.

Surge Protection and Lightning Arrestors

Supplementary to EMI/RFI/EMC Immunity of an Equipment. Many Installations are subject to Highly Disruptive Electrical Environment not just EMI. Depending on the budget and the situation a solution has to be found. Sometimes a CVT or an Isolation Transformer can do a lot of good.

Converting all Energy inputs to battery energy and having a Isolated Synthetic Sine Supply may be an expensive but good solution. Either way the devices that face the harsh environment have to be over rated along with these protections. - delabs design Notes

Earthing Practice and Power Quality

"Earth leakage currents arise mainly from the EMC filters built into electronic equipment with switched mode power supplies. Standards limit the leakage current from non-fixed equipment (i.e. equipment that plugs into a standard socket outlet) to less than 3.5 mA. When a lot of electronic equipment is in use, the total leakage current in the protective conductor can become significant."

Earthing Practice by Trevor Charlton