LED FLICKERING

SpudMuffin

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I have installed new LED lighting in my friend's dentist office. There are 2 circuits that are attached to equipment in the basement. When that equipment starts up the LED's in certain rooms flicker for a few seconds when the draw of the starter on the motors or printers start up. It is VERY annoying to the workers and patients. It was not evident with the older flourescents or incandescent lights. Any suggestions?
 

MeMeMe

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I have installed new LED lighting in my friend's dentist office. There are 2 circuits that are attached to equipment in the basement. When that equipment starts up the LED's in certain rooms flicker for a few seconds when the draw of the starter on the motors or printers start up. It is VERY annoying to the workers and patients. It was not evident with the older flourescents or incandescent lights. Any suggestions?

Did you put in name brand commercial quality lighting (Eaton, Acuity-Lithonia, Philips, etc.) or off-brand, import product?
 

PhotonWrangler

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Sounds like a voltage regulation problem which points to the ballast. You need a better ballast or power supply that has some beefy electrolytic capacitors in it for filtering out the voltage sags.
 

idleprocess

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I've got a similar problem in the home office whenever the laser printer spools up. I print rarely so I just deal with it.

WRT the OP's situation, need to know the setup. PnP LED floro retrofit tubes being fed by a ballast are likely to be an issue since they're at the mercy of the ballast's behavior.
 

PhotonWrangler

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Our office was recently converted to 100% LED lighting. These are purpose-built fixtures, not fluorescent retrofit lamps. Name-brand ballasts on all of the fixtures. I haven't seen a single flicker and I'm pretty sensitive to it.
 

MeMeMe

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Sounds like a voltage regulation problem which points to the ballast. You need a better ballast or power supply that has some beefy electrolytic capacitors in it for filtering out the voltage sags.

Capacitors in a power supply/LED lamps are going to keep the output "up" for 10's of milliseconds, not the "few seconds" the op says the issue exists. This is a noise issue. You could try a hefty in line EMI filter, one for smoothing, not so much surge/spike reduction.
 

idleprocess

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Our office was recently converted to 100% LED lighting. These are purpose-built fixtures, not fluorescent retrofit lamps.
Generally the way to go for performance and longevity. However, with the low cost of LED tubes and the ubiquity of the T12/T8 fixtures across commercial and industrial spaces, I'm not sure if it's the way to go for optimal ROI.

Name-brand ballasts on all of the fixtures.

This might be a quibble, but in my experience, ballast generally means a device that operates an arc lamp such as a fluorescent tube, metal halide, sodium vapor, mercury vapor lamp, etc that requires a high-voltage DC pulse to start the arc then a lower operating voltage once the arc is established. These are generally standardized by lamp type and largely interchangeable.

LED fixtures have drivers in my experience which tend to be far more tightly integrated into the fixture, and since the manufacturers have little incentive to commoditize their business through standard interchangeable components (i.e. the Zhaga consortium that's seemingly failed to launch) cutting into their margins selling whole fixtures or proprietary spares.

So I'm confused by "name-brand ballasts" in purpose-built LED fixtures.
 

PhotonWrangler

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Idleprocess, my bad. I meant to say LED drivers such as these. The external appearance resembles a ballast somewhat, but it is a completely different type of circuit as you've correctly pointed out.
 

idleprocess

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Idleprocess, my bad. I meant to say LED drivers such as these. The external appearance resembles a ballast somewhat, but it is a completely different type of circuit as you've correctly pointed out.

To be fair, in broad common usage, almost any device needed to operate a light source off anything other than the source voltage (120/240VAC household/office mains or 12VDC automotive) is often referred to as a ballast.

My principal confusion was that these have become semi-commodity devices somewhat external to the rest of the lighting fixture? I guess the value for the fixture designer/manufacturer isn't in developing the in-house know-how for power electronics but in the fixture aesthetics and function. Perhaps commoditization is happening anyway.
 

PhotonWrangler

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To be fair, in broad common usage, almost any device needed to operate a light source off anything other than the source voltage (120/240VAC household/office mains or 12VDC automotive) is often referred to as a ballast.

My principal confusion was that these have become semi-commodity devices somewhat external to the rest of the lighting fixture? I guess the value for the fixture designer/manufacturer isn't in developing the in-house know-how for power electronics but in the fixture aesthetics and function. Perhaps commoditization is happening anyway.

I've seen a lot of them being used with LED strips for roll-your-own decorative and accent lighting. This seems to be turning into a large enough market to warrant selling the drivers separately.
 
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