Flourescent lights make the radio static.

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Buck Parrish

Buck Parrish

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We installed new fluorescent lights in a metal building and the customer is complaining that he can't play a radio for the noise emanating from the ballasts! Battery Radio or a plug in 120V.

The radio plays fine with the lights off.

The lights are in a vapor / dust proof cover. The eight ft. long lights have four 4 ft. T8 bulbs. The industrial building is metal with exposed metal beams. No sheetrock.

Anyone ran into this and have a solution?

Thanks
 
I think he needs an outdoor antenna. I thought the lights were not supposed to interfere with radio but I have noticed the same thing in a building I was just working on......wood frame with a metal roof FWIW.

I'm a radio guy and have a local station I love that I would not give up for anything on pandora or i heart......don't even talk about sirius, I have had the chance to play with that in a couple of rental cars on spring break trips, worse than cable tv....57 channels and nothing I could stand to listen to for more than ten minutes.
 
Buck Parrish said:
We installed new fluorescent lights in a metal building and the customer is complaining that he can't play a radio for the noise emanating from the ballasts! Battery Radio or a plug in 120V.

The radio plays fine with the lights off.

The lights are in a vapor / dust proof cover. The eight ft. long lights have four 4 ft. T8 bulbs. The industrial building is metal with exposed metal beams. No sheetrock.

Anyone ran into this and have a solution?

Thanks
Click to expand...
I have had this problem quite often ever since electronic ballasts started becoming the mainstream over magnetic ballasts. Haven't found any solution other then extending the antenna outdoors usually works. Most newer cordless tool battery chargers also interfere with radios - even with jobsite radios that have built in battery chargers for charging the tool battery they are associated with:roll:
 
These new lights we installed are ridiculous. You can't hear the radio at ALL. They have been leaving the lights off..

. The owners have been listening to the radio for over 30 years and they do not intend to quit. They had huge sky lights cut in
Their are radios by every ones work station.... Should we have installed another type light instead? ... Also I just realized my basement radio has not been working well since I installed a work light.

Something needs to change. I won't be recommending new lights that screw up everybody's radios.
Thank god for blue tooth.
 
150516-0952 EDT

Try a Corcom 5VR1 filter inside the fixture. This may reduce the noise going into the wiring that supplies the fixture. This wiring may become an antenna (radiation) or conduct noise to a cord attached radio.

This won't do anything for noise radiated directly from the fluorescent tubes.

Inside a building with metal in the ceiling or walls may greatly reduce the incoming radio signal.

My breezeway has a plaster ceiling with metal lath. I can have a clean signal outside of the breezeway from WJR (a 50 kW station), but as I come into the breezeway I get background noise from my dimmers. Virtually all my fluorescents have the 5VR1 or equivalent filter. The WJR signal strength is substantially reduced by the metal lath. Thus, because of the shielding of the lath the signal to noise ratio gets worse.

.
 
Are the ballasts FCC class A or B?
There have been many ballasts sold that do not comply with the FCC radio interference rules. In a couple of cases that I am aware of, the interference shut down public safety repeaters located close by. I think those cases were actually LED drivers and not ballasts.
 
don_resqcapt19 said:
Are the ballasts FCC class A or B?
There have been many ballasts sold that do not comply with the FCC radio interference rules. In a couple of cases that I am aware of, the interference shut down public safety repeaters located close by. I think those cases were actually LED drivers and not ballasts.
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There's a magnitude difference or so in the permissible RFI between FCC part A vs B ballasts with the latter being the lower and approved for residential use. Some LEDs are even worse RFI emitter due to the way the LEDs are controlled (PWM)

Metal roof already attenuates incoming radio reception without any assistance, so it reduces the signal strength relative to the noise.

Make sure the roof, ballast and fixtures are correctly grounded. Proper grounding is important in RFI situations.
 
I too have t-8 fluorescent fixtures in the shop and every time I turn them on it practically knocks out all radio reception except for the local channel.
I don't care if a ballast or driver is class A or B it should plain never interfere with radio frequencies to that degree!
Something does need to be done about it, customers also complain of it happening.
 
outside antena, any suggestions ?

outside antena, any suggestions ?

Yes , thanks
These owners want me to put some type of antennae out the top of the building. Any suggestions?
I thought about installing a PVC pipe above the roof. With a car antennae on top of it, But I'm not sure that would eliminate the inteference. Not unless we used some type of coaxle.
 
One could just use a temporary extension wire routed out a door or window just to see how much improvement you get in reception and go from there, sometimes that may be enough to do pretty well. But the shield on the coax will help where the lead runs through interference zone.
 
Threadstarter, you didn't mention which radio was affected. AM or FM?

mopowr steve said:
I too have t-8 fluorescent fixtures in the shop and every time I turn them on it practically knocks out all radio reception except for the local channel.
I don't care if a ballast or driver is class A or B it should plain never interfere with radio frequencies to that degree!
Something does need to be done about it, customers also complain of it happening.
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Generally, the worst offender is PWM LED driver. They control the LEDs by rapidly mashing the gas pedal and letting off which actually lets them squeeze out a better lm/W performance, but generally not able to meet FCC regulations for residential use.

Where the interference occurs depends on the frequency of emissions vs the frequency of affected devices. AM radio, FM radio, VHF and UHF are affected by different bands. FCC part B ballasts are specifically intended for residential use where they're meant to co-exist in close proximity with radios and TVs.

There are special lenses or fixtures that use a tinted lens kind of like very mildly tinted windows to further reduce RFIs and used for recording studios and such. Magnetic ballasts are still available new and legal for special applications such as recording studios and medical facilities with sensitive equipment.

The first thing I would check is the grounding between the ballast and fixture, fixture grounding, and roof and metallic building structure grounding. Having all the wires run in grounded metal conduit can help contain radiated interference and conducted be mitigated by a suppression device on the branch circuit.
 
The static is on AM and FM, battery or wired. We got the lights at Home Depot. We grounded every thing properly and even upsized the neutral. It's a metal building with all metal emt conduit with compression couplings. The lights are no good for nothing. The owners are very mad.

I can't believe UL would let this sorry of a product past their listing process. The lights are total garbage. It doesn't matter residential or commercial. Most everybody has a radio.
 
Buck Parrish said:
The static is on AM and FM, battery or wired. We got the lights at Home Depot. We grounded every thing properly and even upsized the neutral. It's a metal building with all metal emt conduit with compression couplings. The lights are no good for nothing. The owners are very mad.

I can't believe UL would let this sorry of a product past their listing process. The lights are total garbage. It doesn't matter residential or commercial. Most everybody has a radio.
Click to expand...

What's the brand and how many do you have?

I ask, because quantity affects the intensity of noise in the same sense that if you had ten radios playing, it would be louder than 1. The impact of noise would be greater when the signal is weaker and metal roof will weaken the signal. How's the reception with the lights off? Do you get all the stations as well as you do outside or is it marginal?
 
Buck Parrish said:
The static is on AM and FM, battery or wired. We got the lights at Home Depot. We grounded every thing properly and even upsized the neutral. It's a metal building with all metal emt conduit with compression couplings. The lights are no good for nothing. The owners are very mad.

I can't believe UL would let this sorry of a product past their listing process. The lights are total garbage. It doesn't matter residential or commercial. Most everybody has a radio.
Click to expand...
That sucks for sure. Grounding and grounded conductors got nothing to do with the the problem. Sounds like your best hope is to add a filter like Gar suggested but I don't know how one goes about doing it.
 
Buck Parrish said:
The static is on AM and FM, battery or wired. We got the lights at Home Depot. We grounded every thing properly and even upsized the neutral. It's a metal building with all metal emt conduit with compression couplings. The lights are no good for nothing. The owners are very mad.

I can't believe UL would let this sorry of a product past their listing process. The lights are total garbage. It doesn't matter residential or commercial. Most everybody has a radio.
Click to expand...
GE has a paper that suggests better bonding between the fixture enclosure and the ballast enclosure may help.

As far as UL, they look as safety issues, not performance issues.

The commercial vs residential issue is an FCC issue. They permit more radio interference on equipment intended for commercial use.
 
We threw the boxes away. It's only 8 lights. But each light has four 4ft tubes. I'll check out the brand and get back to you all.
We're going to be forced to replace them. But with what?

I think we're going to stop credit card payment to see if we can get their attention. .

As far as safety goes. If your not listening to the radio. You could miss an emergency broadcast. Say if a meteorite was going to hit the earth. Or if a local train had spilled dangerous chemicals. You'd miss it and could perish simply because you had no radio to warn you.

In this case, the owner likes to listen to talk shows. I forgot the name, but it starts with an R or Rush something like that. The title sounds like a 70's rock and roll band to me.
 
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