EMI Filters for Industrial Automation
Industrial automation systems such as VFDs, servo drives, PLCs, robots and switching power supplies can generate significant conducted EMI that affects control stability and EMC performance.
DOREXS provides industrial EMI filters and application-specific EMC solutions for single-phase, three-phase and DC power systems.
With the continuous improvement of intelligent manufacturing and automation levels, high-frequency inverters, servo drives, PLC control systems, etc. in industrial equipment will generate a large amount of electromagnetic interference (EMI), which not only affects the stability of the equipment itself, but may also cause failure of peripheral systems and even cause safety accidents.
Order your customized EMI filter solutions
DOREXS EMI filters can effectively suppress conducted and radiated interference, meet the stringent requirements of industrial environments for electromagnetic compatibility (EMC), and help companies pass compliance certifications in global markets (such as CE, UL).
Industrial Equipment & Typical Applications
DOREXS industrial EMI filters are used across a wide range of automation and power-control equipment.
Servo motors and servo drives
VFDs and soft starters
Industrial robots and robotic arms
Automated conveying and packaging lines
Precision machining machine tools
Industrial power supplies and control cabinets
Recommended Industrial EMI Filter Solutions
DOREXS provides different EMI filter configurations for industrial equipment based on power system, current level, noise source, installation space, and EMC requirements.
Suitable for low-power control modules, small drives, or signal devices in industrial automation, ensuring stable system operation.
Suitable for high-power load equipment in industrial automation, especially inverters and servo systems, providing excellent common-mode and differential-mode interference suppression.
DOREXS VFD EMI filters suppress high-frequency conducted noise generated by variable frequency drives, helping improve EMC performance, reduce interference.
Provides customized services for specific equipment or complex operating conditions, including customization of current, voltage, interfaces, and dimensions.
How to Select an Industrial EMI Filter
Selecting the correct EMI filter should be based on the actual operating conditions of the equipment.
Key factors include:
✔ Operating voltage
✔ Rated current
✔ Single-phase / three-phase / DC system
✔ Equipment type
✔ Noise source
✔ Switching frequency
✔ Leakage current requirements
✔ Motor cable length
✔ Installation space
✔ Grounding method
✔ Required EMC performance
For VFD and servo systems, engineers should also consider motor power, switching frequency, cable length, grounding conditions, and common-mode current.
For PLC cabinets and control systems, compact single-phase or DC filters may be more suitable.
EMI Source & Recommended Solution
EMI Source
Typical Problem
Recommended Solution
VFD PWM switching
Conducted common-mode & differential-mode noise
Three Phase / VFD EMI Filter
Servo amplifier
Encoder or PLC interference
High-Attenuation EMI Filter
Switching power supply
Power-line noise
Single Phase EMI Filter
DC converter
DC conducted emissions
DC EMI Filter
Long motor cable
Common-mode current and radiated coupling
Input EMI Filter + Grounding Optimization
Industrial control cabinet
Mixed power and control noise
Single Phase / Custom EMI Filter
EMI Filters Designed for Industrial Use
Industrial automation equipment such as VFDs, servo drives, PLC systems, CNC machines, and switching power supplies can generate significant conducted electromagnetic interference.
Selecting the right EMI filter depends on the equipment type, power system, operating voltage, rated current, noise characteristics, and installation environment.
DOREXS provides single-phase, three-phase, VFD, DC, and custom EMI filters for industrial applications. These filters help reduce common-mode and differential-mode noise, improve EMC performance, and protect sensitive control, communication, and measurement circuits from power-line interference.
For VFD and servo systems, filter selection should consider switching frequency, motor power, cable length, leakage current, and grounding conditions. For PLCs, control cabinets, and industrial power supplies, compact single-phase or DC filters may be more suitable.
EMC Standards & Compliance Support
Industrial equipment must meet different EMC requirements depending on the equipment type, power system, application environment, and target market.
Relevant standards may include the IEC/EN 61000 series for electromagnetic compatibility, EN 55011 / CISPR 11 for industrial equipment, and IEC 61800-3 for adjustable-speed electrical drive systems such as VFDs and motor drives.
EMI filters used in industrial equipment should be selected according to the applicable system-level EMC requirements rather than relying on a single universal standard.
DOREXS supports industrial customers with EMI filter selection, application guidance, and compliance-oriented filtering solutions based on equipment voltage, current, noise characteristics, installation conditions, and EMC test requirements.
Selected DOREXS product series are available with applicable certification and compliance options according to product type and market requirements.
Why Choose DOREXS for Industrial EMI Solutions?
DOREXS combines EMI filter manufacturing with application-oriented engineering support for industrial automation and power-control equipment.
Broad Industrial EMI Filter Range
Single-phase, three-phase, VFD, DC, high-current, and custom EMI filtering solutions are available for different industrial power systems.
Application Engineering Support
Filter selection is based on equipment type, voltage, current, EMC problem, installation conditions, and system requirements.
Custom Design Capabilities
Electrical and mechanical customization is available where standard filters do not fully meet application requirements.
Quality & Electrical Testing
Product inspection and testing may include: electrical performance testing, withstand voltage (Hipot) testing, leakage current testing, insertion loss verification, and visual and mechanical structure inspection.
Compliance Support
Selected product series are available with applicable certification and compliance options according to product type and market requirements.
Industrial EMI Filter Technical Resources
DOREXS provides technical resources to support industrial filter selection, equipment design, EMC troubleshooting, and project evaluation.
Available Resources
✔ EMI Filter Datasheets
✔ Product Catalogs
✔ Certification Documents
✔ Selection Guides
✔ Installation Guides
✔ EMC Technical Articles
✔ Industrial Application Case Studies
Need Help Solving an Industrial EMI Problem?
Not sure which EMI filter is suitable for your equipment?
Send us:
Operating Voltage + Rated Current + Equipment Type + EMC Problem + Installation Space
Our engineering team can help evaluate your application and recommend a suitable standard or custom EMI filtering solution.
Frequently Asked Questions
Three-phase or dedicated VFD EMI filters are commonly used at the AC input of variable frequency drives. The correct filter depends on drive power, voltage, current, switching frequency, cable length, and EMC requirements.
Servo systems typically use three-phase high-attenuation EMI filters. Filter selection should consider servo amplifier current, motor power, grounding conditions, encoder sensitivity, and system EMC requirements.
EMI filters can help reduce power-line noise that may contribute to PLC resets or unstable control behavior. Grounding, shielding, and wiring layout should also be evaluated.
In most industrial applications, the filter should be installed close to the equipment power input, with short wiring and good grounding to reduce unwanted coupling.
Yes. DOREXS supports customization of voltage, current, filter topology, attenuation performance, leakage current, terminals, housing size, mounting method, and other electrical or mechanical parameters.
DOREXS is an expert in electromagnetic solutions, making your equipment (brand) more competitive in the market.