Solve flickering LED strips

It’s the LED professional’s nightmare : You finish the install, turn on your strip lights, and encounter the dreaded LED light strip flicker. What should be a smooth and even glow looks like a busted neon sign. Luckily for your client you’re an LED professional (you’ve read this very blog post) and you know how to solve LED flickering issues.

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Flickering is caused by a handful of different reasons, and once you’re aware of the causes it’s easy to identify and solve the issue. Those reasons, ordered roughly in descending order of frequency, are poor connections, incompatible parts, voltage drop due to long runs, and defective or overloaded power sources. They’re all relatively easily solved. Below we’ll talk about how.

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1) Poor connections

Read more about connector troubleshooting here

Diagnosis : Flicker begins (or significantly worsens) after a connection.
Cause : A poor, inconsistent, or intermittent connection can cause flicker by alternately making and breaking the electrical circuit. Almost exclusively present in solderless connectors (not in soldered or spliced connections)
Tests : Moving the strip around in your solderless connector will change the amount of flicker or even temporarily stop it from occurring at all.

Solution : Fix the connection! Check out our solderless connection troubleshooting tips or consider soldering. Advice on both available on our blog post here.

2) Incompatible parts

Read more about dimmer compatibility here

Diagnosis : Flickering across entire strip that is affected by the level of dimming.
Cause : Incompatible dimming protocols (eg PWM vs CCR or Magnetic vs Electronic) causing fluctuations in voltage and/or current.
Tests : Removing any dimmers or controllers from the circuit causes the flicker to stop.

Solution : Make sure everything is compatible! If you’re using a dimmable driver, note that dimmers or controllers on the low voltage side are NOT compatible. If you’re using a non-dimmable driver, note that any dimmer switches on the high voltage side are NOT compatible. If you’re using a dimmable driver, make sure the dimmer switch you’re using is compatible.

3) Voltage drop

Read more about voltage drop here

Diagnosis : Flickering across the entire strip that is accompanied with a significant decrease in brightness across the strip
Cause : Excessive run length causing voltage drop leading to both dimming and flickering
Tests : Remove sections of strip from the end of your run should improve both dimming and flickering.

Solution : Minimize your run length! LEDs have a minimum voltage requirement. Excessive run length not only causes dimming and possibly flickering due to voltage drop, it can cause excessive load and wear on strips, connectors, and power supplies. Consider powering your strip from the middle of the run or otherwise break it up into smaller sections. This blog tackles dimming caused by voltage drop but since the cause is the same for flickering, all advice is valid for both issues.

4) Overloaded or defective power supply

Read more about sizing a power supply here

Diagnosis : Flickering across the entire strip that is accompanied by a noisy or hot power supply
Cause : Excessive load or defective power supply causing voltage fluctuations
Tests : Replace power supply

Solution : Swap out the power supply or minimize your run length.

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Flickering solved? You’re now an LED expert! Pat yourself on the back and bask in the glow of your smooth and even LED strip lighting.