[RFI] Low Voltage Lighting Questions

[Cortland Richmond]

Do post the ratings on the "FCC Approved" transformer; there may be less 
expensive substitutes.

Cortland
ka5s

On 3/30/18 3:16 PM, David Eckhardt wrote:

> We had a couple of task lights installed.  They are 12 volt high-intensity
> incandescent  lights.  Each fixture came with its own 'electronic
> transformer' - a.k.a. switcher.  The 120 vac was switched, not the 12 vac.
> Long story, but I had to pay $48 EACH for an "FCC approved" transformer.
> The regular 'electronic transformers' cost $4.95 and produced lots of RFI.
> The expensive "FCC approved" units were surprisingly quiet.  But, at what a
> price!
>
> Any screw-in LED lighting I have seen has the switcher installed in the
> screw-in or plug-in base and is standard.
>
> Dave - WØLEV
>
> <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail&utm_term=icon>
> Virus-free.
> www.avast.com
> <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail&utm_term=link>
> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
>
> On Fri, Mar 30, 2018 at 5:54 PM, Jim Stahl via RFI <rfi at contesting.com>
> wrote:
>
>> I’ve determined that I have one or more LED kitchen track/ceiling light
>> installations in nearby condos that are causing RFI. Killing the breaker
>> kills the RFI.
>>
>> Since these are in condo units occupied by renters, I need to go through
>> the owners (fortunately who live locally) to do anything about remedying
>> the RFI. So I want to know what to expect when I am able to get access for
>> more than killing breakers.
>>
>> Are the low voltage supplies (which I assume are the problem) powered
>> 24/7, with the light switch/dimmers being on the low voltage side of the
>> supply?
>>
>> Are the dimmers pulse width modulated, or amplitude modulated? Are the
>> dimmers in these LED systems likely to be a problem themselves?
>>
>> Are these supplies normally equipped with a standard electrical plug into
>> a normal outlet? Is there normally accessible low voltage wire between the
>> supply and the start of the lighting chain? I.e. are there likely to be
>> issues with installing ferrites on either side of the supply?
>>
>> Is 12 volts DC a common or standard low voltage level? What is the
>> approximate DC current per bulb, i.e. if I were to replace the RFI
>> generating switching supply with a linear supply, how big of a supply would
>> normally be needed?
>>
>>
>> Thanks & 73  -  Jim   K8MR/4
>>
>>
>> _______________________________________________
>> RFI mailing list
>> RFI at contesting.com
>> http://lists.contesting.com/mailman/listinfo/rfi
>>
>
>