The EMI EMC filters are made in a certain measure to make certain compliance of products with EMC requirements. Thus, they can work effectively if they are properly installed. Installation is important to filter performance because appropriate installation helps in minimising the propagation and susceptibility to interference. This helps in achieving compliance with standards and regulations. EMI filter installation best practices typically reduce overall costs of compliance by reducing repeated testing costs and optimizing the solution. The planning and implementation of other EMC measures and design rules also contribute to good performance in terms of noise emission.

Best Installation Practices:

1. EMI Filter wiring and cable layout:

• Make sure filter output wires are not routed close to or near the input wires.
• Maintain physical isolation and separation between filter input and output wires.
• Make sure to keep power wiring separate from control wiring. Power and control wires must not run in parallel. Keep control wires away from the incoming power lines to the filter. If the input and output line is nearby, noise is generated at a high frequency, affected by electric induction.

An ideal isolation system is a bulkhead-mounted filter incorporating a line cord connector, such as the Elcom EB power line filter series. For the connection keep wires/cables at the filter input as short as possible and shield the input cables, if necessary.

2. EMI filter mounting:

The mounting and wiring of the filter are critical things which have influenced its performance. So, its purpose must not be defeated by stray capacitance coupling the power input leads to the power output leads, or to any other conductors in the protected equipment. So, mount the filter as close to the EMI source as possible and ensure that the filter input and output conductors leads are separated, whether it’s a drive, uninterruptible power source, inverter, or another component.

3.EMI filter Grounding:

Another important requirement is its connection to the ground. Use shielded wiring wherever possible and connect the system ground to the EMI filter. Proper grounding is very essential for the operation of the filter. Without correct grounding, the filter will lose the common-mode attenuation provided by Y-capacitors. Ensure filter housing is grounded to the host cabinet by metal-metal connection. All surfaces are to be conductive and void of paint or other insulating material. For non-metal housings, the filter should be grounded by the incoming safety wire. Take a ground wire as thick and short as possible and fix the grounding strongly. This will help to achieve a low impedance ground at high frequencies. Mount the filter directly to a bare metal grounded panel for best performance. Use shielded conductors to minimize radiated high-frequency noise levels.

EMI Filter Applications:

Here are some industrial and residential applications of EMI EMC Filters –

• Appliances and washing machines: White goods EMI filters suppress electromagnetic noise for a variety of home appliances from washing machines to treadmills. These filters ensure that devices meet electromagnetic compatibility regulations and help to protect them from EMI damage that can impact their performance.
• Single-phase: Single-phase EMI filters are effective for smaller equipment, such as home appliances and electronics, as well as industrial applications, such as food service equipment, power supplies, and telecommunications. A single-phase EMI filter can also be compatible with fitness equipment and motor controls.
• Three-phase: For more stringent EMI suppression, three-phase EMI filters can block higher levels of noise through a two and three-stage filtering system. Three-phase EMI filters are for use in high-power applications such as industrial machinery and motors, medical equipment, test equipment, and industrial tools.
• Military: EMI filters for military applications specifically meet regulations and compliance standards for EMC of military devices. These reliable EMI filters protect against damage to aerospace and military communication systems for secure operations.
• Medical-grade EMI filters: Medical-grade EMI filters are used for medical applications to protect sensitive medical equipment from damage. Medical grade EMI Filters are available with low leakage current. Effective and reliable EMI filters for medical applications can be life-saving protection against electromagnetic noise interference to the equipment.