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E lectromagnetic Interference (EMI) also known as Radio Frequency Interference (RFI) happens when something disrupts the optimal performance of electrical circuits. The EMI ‘noise’ can be generated in many different ways both man-made and by natural phenomena. Human examples of EMI can be attributed to ignition systems, cellular networks, and solid-state lighting. Natural examples would be lightning, solar flares, and aurora (northern and southern lights). Consider EMI as a form of pollution such as Carbon Dioxide that can’t be entirely eliminated, but can be managed and regulated.

What are the Effects of EMI?

EMI can produce unwanted behavior in many common products we all use on a daily basis. From garage door openers failing to open or opening unintentionally, to pacemakers getting off sync, static on TV’s and radios, WiFi devices failing to communicate, and more. If there is a sufficiently strong interference signal near sensitive equipment with electrical circuits that happen to overlap the frequencies being used, signals can become scrambled. Think of it as trying to carry on a conversation in a room full of rowdy sports fans at a local bar on a Saturday night. With so much shouting and screaming, it would probably be more difficult to for you and a friend to communicate with each other. Interestingly enough, while this all sounds bad, this signal jamming is actually considered an effective method of electronic warfare between nations.

Consider the Electromagnetic Spectrum, it contains the entire band of frequencies of electromagnetic radiation and their respective wavelengths and photon energies. Visible light is a small slice of this spectrum but it also contains everything from Gamma radiation to Extreme low-frequency (ELF) radio waves. Various electronic components are designed to operate within thin bands on this spectrum. EMI doesn’t care where it operates, thus lies the problem.


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So what effect does EMI have on landscape lighting?

Some landscape lighting can generate excessive EMI, negatively affecting transmitting devices such as garage doors, gate openers, and other appliances. In some cases, extreme EMI can cause nuisance tripping in ARC fault breakers. EMI is also cumulative. One fixture or lamp could interfere with nearby electronics or multiple lamps.

Can I mitigate EMI?

As mentioned earlier, EMI can’t be eliminated entirely, but it can be managed. Just as the US Department of Transportation has regulated carbon monoxide emissions in automobiles, the US Federal Communications Commission (FCC) has defined which frequencies electronic devices are allowed to operate on. By limiting the operating ranges of various electronics, the chances of signals being stepped on (EMI) are reduced.

It is the lighting manufacturer’s responsibility to minimize EMI generated in solid-state lighting (SSL). Circuits need to be designed properly with the correct filtering components and tested for FCC compliance.

However, not every manufacturer does adhere to these guidelines. It can be costly to incorporate the appropriate filtering components into their products, and additional testing adds to the cost of the final product as well. It’s unfortunate, but many manufacturers will mark their products as compliant even though they are not.

Additionally, there are few if any components that can be added to the finished lighting setup to eliminate EMI. The products in use need to be intentionally designed with EMI compliance in mind. Aftermarket filters and ferrite cores are largely ineffective in resolving EMI issues.

In Summary:

Not all lighting products are created equally. If the price for a product seems too good to be true, it is possible that shortcuts were taken in the production process that could adversely affect some other electronic components on your property. At EmeryAllen we follow the guidelines set by the FCC to ensure our products comply with regulations. If you have any questions or would like us to help you make a choice based on your needs, please feel free to reach out to us. We’d be happy to help!