EMI Noise Filters

We offer EMI Noise Filters with 275V or 475V input voltage.

Electromagnetic Interference (EMI) is simply noise interference caused by external electromagnetic waves. EMI can lead to the performance degradation of any electrical equipment design within range by inducing unwanted currents and voltages in its circuitry.

These effects can be mitigated with an EMI filter - an electronic component that provides electromagnetic noise suppression for electronic devices. This filter is typically used together with shields and other types of protection. EMI filters only extract and remove offending noise components that can cause electromagnetic noise from electric currents that conduct through electrical wiring.

Apart from using them to protect their electronic devices, designers need EMI noise filters to meet regulatory agency requirements for RF/wireless devices for use in the USA (FCC), Canada (IC), Europe (CE), and many other countries. These dictate that radiated and conducted emissions be constrained below specified limits and must pass immunity/transient requirements. Designers need to understand that EMI noise filters will help in meeting immunity and fast transient requirements as well as radiated emissions to achieve a robust design.

Our EMI noise filter manufacturers’ offerings include the following types:

Sensata/Crydom’s 1F25 EMI noise filter is for use with SSRs in single-phase systems. The AC filter connects between incoming lines of the main supply, reduces conducted noise by around 30dB and is easily added to existing designs.

The 3F20 is similar to the 1F25, but for SSRs in three-phase systems.

Murata’s block type "EMIFIL" BNX series incorporates a through-type capacitor, monolithic chip capacitors and bead. The high performance BNX is for use in DC power circuits.

The filter provides a high insertion loss in a wide frequency range from 0.5MHz to 1GHz. It is effective against impulse noise such as electrostatic discharge or spikes.