Does LED lighting cause interference?

[NB Alnwick]

I often lose the signal from my Vodafone dongle (software reports "No device") just after switching an LED unit on or off - I have also notice that our DAB radio signal starts to 'flutter' when LED units are switched on. Is this normal?

[churchward]

I often lose the signal from my Vodafone dongle (software reports "No device") just after switching an LED unit on or off - I have also notice that our DAB radio signal starts to 'flutter' when LED units are switched on. Is this normal?

It can happen with any device but the LEDs if they don't have radio suppression ( an EC requirement so only cheap grey imports are a problem) can causew problems. However, any device that is switched on can momentarily cause a radio or supply spike. Our sureflo water pump can make the Digital TV pixalate for a second or two.

[alan_fincher]

It can happen with any device but the LEDs if they don't have radio suppression ( an EC requirement so only cheap grey imports are a problem) can causew problems.

 

In view of his previous pronouncements on such matters, I can't imagine Graham, knowingly buying cheap grey imported anything!

[Rog]

I don't believe that LED lights cause any interference in radio frequency terms, but I have found that DAB radios and digital TVs are susceptible to minor power supply "blips". For example, my DAB radio goes quiet for a moment when the toaster finishes toasting (they're both plugged into the same socket).

 

Do you mean interference (ie long term) or "blips" when switcing on and off?

[Chalky]

Depends how they control the LED current. Cheap ones will use a resistive dropper so there's not a problem. More expensive ones will use either a chopper or a switching power supply. If these aren't suppressed properly then they will cause radio interference (either radiated or coupled into the boats wiring). There have been several threads discussing this topic and there are some fixes mentioned.

[Rog]

Chalky, you're absolutely right of course. I'd assumed that in 12v NB situations, resistive droppers would be used. If more efficient circuits (as used in caving lamps, for example) were employed, RF could indeed be a problem. As a newbie, I'll wind me neck in! Didn't realise that previous posts had covered the subject

[Timleech]

I don't believe that LED lights cause any interference in radio frequency terms, but I have found that DAB radios and digital TVs are susceptible to minor power supply "blips". For example, my DAB radio goes quiet for a moment when the toaster finishes toasting (they're both plugged into the same socket).

 

Do you mean interference (ie long term) or "blips" when switcing on and off?

 

I have an expensive German made LED worklight on my big lathe, FM radio is unlistenable when it's on. Admittedly reception is not brilliant here.

Incidentally if my mobile phone rings when it's near the television (digital) we lose the picture, despite the aerial being on the (house) roof.

 

Tim

Edited June 5, 2011 by Timleech

[bottle]

Our LED's cut out the DAB signal completely.

 

Do not affect dongle.

 

Graham

 

Have had the same problem 'no device', 'connect device' etc with Orange dongle, most likely due to poor signal, I can select '2g only' usually sorts it but of course much slower.

[Grace and Favour]

We've now replaced all our halogen bulbs with LED's and, (apart from a couple of 1950's Aladdin Mantle lamps) we have no other form of lighting.

 

I have to report that we've never experienced any form of interference on the DAB radio (a little Roberts), even though I use it right next to my reading lamp!

 

(and I only paid about £6 for the bulbs too, IIRC)

Edited June 5, 2011 by Grace & Favour

[nicknorman]

Chalky, you're absolutely right of course. I'd assumed that in 12v NB situations, resistive droppers would be used. If more efficient circuits (as used in caving lamps, for example) were employed, RF could indeed be a problem. As a newbie, I'll wind me neck in! Didn't realise that previous posts had covered the subject

 

All the led bulb replacements I have seen have switching voltage regulation - bedazzled, BtP etc. They are generally rated up to 30v which is too much power to drop resistively without generating a lot of heat (and wasting a lot of power). Of course a well designed device will have the switching transients suppressed, a badly designed one will radiate a wide spectrum of crap! Depending on the switching speed and sharpness of waveform (ie harmonic content) it might affect some frequencies worse than others, but the wide spectrum of crap can affect spread spectrum devices like 3g (and DAB?) even though spread-spectrum is fairly tolerant of interference at specific frequencies. Moral is to buy quality LED bulbs. We have a mixture of halogen, and LED downlighters from the 2 above sources, and have noticed no impact on 3g (we don't listen to DAB). I suppose it would be possible to add components to remove some of the crap from poorly designed bulbs, but they have small surface mount devices and it would be tricky. Better to buy good stuff in the first place!

 

Nick

 

ETA you could try adding ferrite beads / torroids in the wiring to the bulb (at the bulb) which will substantially reduce the radio interference from using the wiring as an aerial, if that is the primary means of propagation (as opposed to radiating directly from the bulb).

Edited June 5, 2011 by nicknorman

[ditchcrawler]

It can happen with any device but the LEDs if they don't have radio suppression ( an EC requirement so only cheap grey imports are a problem) can causew problems. However, any device that is switched on can momentarily cause a radio or supply spike. Our sureflo water pump can make the Digital TV pixalate for a second or two.

I have one LED light in the back cabin that plays hell with the car radio and it comes from a reputable UK company. So yes they can cause interference big time. I don't know what the effect on the dongle would be as I use my dongle in the lounge so the LED is off

 

We've now replaced all our halogen bulbs with LED's and, (apart from a couple of 1950's Aladdin Mantle lamps) we have no other form of lighting.

 

I have to report that we've never experienced any form of interference on the DAB radio (a little Roberts), even though I use it right next to my reading lamp!

 

(and I only paid about £6 for the bulbs too, IIRC)

I am all LED as well and the LED Busbulb is the only one to cause a problem.

[Keeping Up]

Incidentally if my mobile phone rings when it's near the television (digital) we lose the picture, despite the aerial being on the (house) roof.

 

Our old analogue TV was very prone to interference from the mobile phone. Once Pingu was settling down to watch Eastenders (yes I know!) when our daughter decided to phone her and let her know that the programme was about to start. The phone was near the TV and when it rang, the TV exploded. Pingu didn't get to see Eastenders and I had to buy a new TV.

[Castaway]

LED lighting is pretty much the norm in caravans and motor homes, in the early days some lights did cause FM interference, mainly with the replacement lamp types rather than the 'proper' LED lights. If you shop around, you can buy 'LED' fittings rather than LED replacement lamps which don't tend to perform as well in longevity or light output anyway. On first impressions, a lot of the replacement LED for Halogens look good, but further down the line they tend to loose output with use and may not last as long as an LED product with the appropriate circuitry.

[churchward]

In view of his previous pronouncements on such matters, I can't imagine Graham, knowingly buying cheap grey imported anything!

Quite so, what was I thinking!!

 

I have one LED light in the back cabin that plays hell with the car radio and it comes from a reputable UK company. So yes they can cause interference big time. I don't know what the effect on the dongle would be as I use my dongle in the lounge so the LED is off

 

 

I am all LED as well and the LED Busbulb is the only one to cause a problem.

We are all LED too and a mixture of bulb types. We did buy some reading/wall lights with MR16 LED bulbs in them. They completely blocked out the radio FM or DAB but didn't bother digital TV. We got some new bulbs from Bedazzled (where we got the other bulbs) and all was well. It was the bulbs included by the supplier ( a UK company too) of the lamp fittings that did it. However, as far as I can tell no LED bulb that meets EC spec should provide an radio interference. That being so the bulbs supplied could not have conformed.

[NB Alnwick]

I don't know for certain but I am guessing that most of the available LED units that we have purchased are being manufactured overseas. Nevertheless, I have supported two British companies that supply them, 'Bedazzled' and 'Aten Lighting' - both were represented at the Crick Boat Show and both told me that their products complied with strict EU specifications and should not cause radio interference. Having said all that, I am still not sure because we do get interference when the lights are energised . . .

[Gibbo]

...both told me that their products complied with strict EU specifications and should not cause radio interference. Having said all that, I am still not sure because we do get interference when the lights are energised . . .

 

Unless the radio/TV/whatever is in an area of very low signal strength, anything that does comply with CE standards cannot cause interference.

 

The limits for emissions are absolutely miniscule in comparison to the signal strength from radio stations etc. Typically at least 100 times smaller in an area of normal signal strength. When I run emissions tests on our equipment I have to run the tests inside an electrically sealed steel room because otherwise the transmissions from local WiFi networks, TV and radio transmitters etc completely swamps what I'm trying to measure. eg I might be trying to measure the emissions from our equipment at (say) 2.4GHz which might be at XuV/m (microvolts per meter: a measure of electrical field strength), to make sure it is below the limit of (say) 2.5XuV/m whereas the local WiFis could be producing well in excess of 200XuV/m.

 

If something is interfering with normal use of other equipment you can be pretty certain that what is interfering is either broken or doesn't comply with the standards.

[churchward]

I don't know for certain but I am guessing that most of the available LED units that we have purchased are being manufactured overseas. Nevertheless, I have supported two British companies that supply them, 'Bedazzled' and 'Aten Lighting' - both were represented at the Crick Boat Show and both told me that their products complied with strict EU specifications and should not cause radio interference. Having said all that, I am still not sure because we do get interference when the lights are energised . . .

I doubt any LED bulb is made in the UK. The vast majority will be made in the far east but it is the spec they are built to that is important.

 

All my Bedazzled bulbs work just fine with no interference perhaps I have been lucky but they are throughout the boat.

[Lesd]

Our recessed ceiling LED lights dont interfere at all but our LED reading lights do.

All bulbs from Bedazzled. I'm a bit hacked off that I cant listen to the radio with these lights on !

[Castaway]

You'll probably find LED lights with a 'CE' mark, which isn't really worth a great deal as this is a 'self certify' process. There isn't any recognised European Standard for 12V lighting other than road lighting to my knowledge so the lighting on the market can differ hugely from one importer to another.

 

I would be amazed if any of the 'replacement' LED products are made anywhere other than in Asia, which doesn't make them bad, but will question the practicality/consistency/quality from most sources. Anyone with experience of buying from Asia will know what I mean.

 

As I mentioned before, purchase an 'LED' fitting (A purpose made product) rather than simply swapping lamps and you should be OK. I would also recommend using something found commonly in Caravans and Motor Homes which are probably the nearest comparison to our own environment available. If they are fitting to 20,000+ caravans every year they should be OK. You'll probably find they will cope with more than 12V as well, unlike some of the 'replacement' LED lamp products which may not like 14-15V put through them at times. I've yet to find a Marine LED supplier featuring in Caravans, not sure why but it does concern me a little, are they a lighting expert or exploiting an opportunity?

 

The cost of the replacement LED lamp is often sold providing the retailer with a huge margin, the consumer believes it easier and cheaper than replacing the complete unit for a 'real' LED product. Shop around, you can buy 'real' LED products effectively.

[Smelly]

I'm sat typing via 3g under the cheap chinese imports I bought 4 years ago and have never noticed a problem.

 

The DAB radio is flaky at the best of times but doesn't seem bothered my having just switched across from FM to test it.

[Dominic M]

I've LED lighting throughout the boat. It doesn't affect the DAB radio, or the telly, but it has turned Dan Brown's "The Da Vinci Code" on my Kindle Reader into barely comprehensible illiterate rubbish.

[Smelly]

I've LED lighting throughout the boat. It doesn't affect the DAB radio, or the telly, but it has turned Dan Brown's "The Da Vinci Code" on my Kindle Reader into barely comprehensible illiterate rubbish.

 

I trust this is the first time you've tried reading it...

[Dominic M]

I trust this is the first time you've tried reading it...

[matty40s]

....it's even worse the second time.....

 

 

 

I have gone 90% LED now with a selection of bulbs and LED fittings from a variety of suppliers. There is no interference when I use my DAB or TV. my dongle worked perfectly OK too when I used it although I did have an external ariel. my new WiFi zone HTCWildfire isn't affected either.

 

 

However, my washing machine is a pile of shite so I blame the LED's.

[Dominic M]

Ricky at Bedazzled, who lies just up the canal from Stowe Hill on the other side of Weedon, reckons that in a few years the domestic low energy bulbs we have at present will be history, just as incandescents are now. LEDs will be the lighting. I can't see why not. The quality of light from LEDs is so good now, and the power consumption so low, it seems a no brainer to me.

Edited June 9, 2011 by Dominic M