RFI
[Top] [All Lists]

Re: [RFI] Low Voltage Lighting Questions

To: rfi@contesting.com
Subject: Re: [RFI] Low Voltage Lighting Questions
From: Cortland Richmond <ka5s@earthlink.net>
Date: Sat, 31 Mar 2018 08:22:05 -0400
List-post: <mailto:rfi@contesting.com>
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@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@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi




_______________________________________________
RFI mailing list
RFI@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi
<Prev in Thread] Current Thread [Next in Thread>