EMi Filters
                     ONE STOP SOLUTION FOR 
STANDARD & CUSTOMIZED EMI 
FILTERS
 
EMI
• Electromagnetic interference (EMI)
• There are two main types of EMI — conducted EMI 
and radiated EMI.
• Conducted EMI goes through conductors, such as 
wires or power lines, while radiated EMI travels 
through the air and does not require a conductor.
• Both conducted and radiated EMI can impact the 
performance of electronic devices through 
impairment, degradation, malfunctioning or system 
failure.

• RFI is an acronym for radio frequency 
interference, refers to noise that falls on the radio 
frequency spectrum within the electromagnetic 
frequency spectrum. Meanwhile, EMI refers to any 
frequency of electromagnetic noise.
 
• In other words, RFI is a subset of EMI and includes 
only electromagnetic currents with a frequency 
between 3 kilohertz and 300 gigahertz. Just like 
EMI, RFI can be conducted or radiated and can 
cause a variety of problems with electronic 
devices.
WHAT IS EMC?
• EMC is Electromagnetic Compatibility.
• EMC describes how a device functions or 
performs in an environment of 
electromagnetic noise.
                              EMC includes two 
factors: EMC
 TOLERANCE TO NOISE HOW MUCH NOISE IT 
(NOISE IMMUNITY) PRODUCES
WHERE DOES EMI COMES FROM?
Natura
Man-made EMI is l 
most often the Causes
result of 
electronics or 
electrical circuits, Man-made causes 
but can also of EMI span both 
result from residential and 
switching industrial sectors, 
systems or and some devices 
changes in large can also create 
currents. interference 
Man-Made between internal 
Electrical components.
Devices
                NATURAL CAUSES OF EMI
Naturally occurring EMI can come from a variety of sources, 
including:
Lightning Strikes Solar Flares Cosmic Noise Static Electricity
Atmospheric Solar magnetic 
electrical storms Snowstormsstorms Dust storms
Natural Electromagnetic Interference can occur at anytime and have adverse impact 
on inadequately protected electrical devices. Natural EMI, such as electrical storms or 
solar flares , can harm military equipment or transportation technologies. The sun can 
cause disruptions to satellite transmissions if it appears directly behind a satellite and 
the electromagnetic noise masks the satellite's transmission. On a smaller scale, 
naturally occurring EMI like snowstorms may cause radio static or disrupt cell phone 
signals.
  RESIDENTIAL CAUSES OF EMI (MAN-MADE)
• Cell phones • Microwaves
• Laptops • Heating pads
• Wi-Fi devices • Toaster ovens
• Bluetooth • Electric blankets
devices • Heaters
• Baby monitors
Residential causes of EMI often come from devices that 
operate using a wireless signal, but also emanate from a 
variety of other electronic appliances.
MAN-MADE INDUSTRIAL CAUSES OF EMI
Industrial causes of EMI are often larger-scale and can cause 
severe damage to important technologies.
Some common EMI sources in the industrial sector are as 
follows:
• Electric motors and generators
• Television transmissions
• Cellular networks and telephone transmissions
• Radio and satellite
• Grid power
WHAT IS AN EMI FILTER?
An EMI filter is a passive electrical device consisting of capacitors 
and inductors arranged in a specific circuit to suppress high 
frequency noise propagating along equipment and facility power 
lines. EMI is primarily manifested as harmonic energy/noise 
generated by sharp changes in circuit currents/voltages.
What does an EMI filter do? When 
attached to circuits or devices, it can suppress 
electromagnetic noise transmitted through conduction. 
These filters extract any unwanted current conducted 
through wiring or cables, while allowing desirable 
currents to flow freely. 
How do EMI filters work? Most 
electromagnetic noise is in a higher frequency range, so 
EMI filters are often low-pass filters that sift out high 
frequencies while letting lower frequencies pass 
through. Different EMI line filters suppress specific 
frequencies of noise, while allowing others to flow 
unimpeded. 
At PrEMIer Filters, we have an extensive line of standard EMI 
power line filters and unlimited custom capability to address 
any EMI power line filter requirement. Coupled with our in-
house safety and EMI conducted emissions test labs. 
Products Range:
• EMI/RFI FILTERS
• Three Phase Filters
• Single Phase Filters
• Mil/COTS EMI 
Filters
• DC FILTERS
• Custom Filters
PrEMIer Filters is a global leader in the design and manufacture 
of AC/DC EMI Power Line Filters, for all Environments from 
Military to Industrial to Commercial. With over 50 standard 
product series and unlimited custom capability, Premier Filters is 
uniquely positioned to meet the stringent cost and Schedule 
demands required by today’s market. With manufacturing 
locations in Asia and our prototype/quick-turn production and 
EMI and Safety labs in the USA, Premier Filters has the fastest 
delivery and design to market response in the industry.
PrEMIer Filters is your EMI filter partner.
• MIL/COTS EMI FILTERS  
• SINGLE PHASE EMI FILTERS
• THREE PHASE EMI FILTERS   
• CUSTOM EMI FILTERS
CONTACT US
Premier Filters, Inc.
125 E. Bristol Ln
Orange, CA 92865
Phone : +1-657-226-0091
FAX : +1-657-223-6495
Email : [email protected]
Website: https://www.premieremc.com/