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Re: [RFI] Cree LED Light Bulb

To: "EDWARDS, EDDIE J" <eedwards@oppd.com>
Subject: Re: [RFI] Cree LED Light Bulb
From: Charlie Gallo <Charlie@TheGallos.com>
Reply-to: Charlie Gallo <Charlie@TheGallos.com>
Date: Mon, 11 Aug 2014 15:43:39 -0400
List-post: <rfi@contesting.com">mailto:rfi@contesting.com>
On 8/11/2014 EDWARDS, EDDIE J wrote:

The  Watts  drawn  number  is  at the socket, so include that ballast.
That said, the electronics in said ballast are a LOT more sensitive to
heat than a light bulbs, which is why we discussed "fire" vs failure

> 2 things I haven't pinned down yet:
> What is the normal amount of heat generated by the ballast of CFLs?
> Is ballast heat included on the CFL wattage rating?


> I have heard some CFLs have warnings they should not be used inside
> enclosed fixtures (open fixtures only), and others warn against
> using them mounted upside down.  I assume this is due to ballast heat.  But I 
> could be wrong.

Yes  again.   You  would  have  to  look  for  a CFL that is rated for
enclosed use.

That  said, I've entirely given up on CFLs.  Hate the light, they have
never  lasted  worth  a  darn in the situations I've used them, take a
LONG  time to warm up, and the final stroke - cost almost as much as a
LED light.

I've  got  6 Cree bream warm white dimmable PAR-40 LED bulbs complete with trim 
rings (aka meant for
can  lights)  running  between  the den and living room, and 8 PAR-30s
that  DON'T  include trim rings but are rated for cans/dimmable in the
LR and Den and Kitchen (the LR and den have a mix of each size - PAR40
for  pure  down, and PAR-30 in the eyeball lights).  Had issues galore
with  CFLs in the Den/LR (they were never in the kitchen), but I think
I've lost ONE LED in the last 3-4 years, and those lights are probably
on  8+  hours/day.   I've  never been able to detect a peep out of the
bulbs on RF

> 73, de ed -K0iL

> -----Original Message-----
> From: RFI [mailto:rfi-bounces@contesting.com] On Behalf Of Charlie Gallo
> Sent: Monday, August 11, 2014 1:05 PM
> To: Peter Laws
> Cc: rfi@contesting.com
> Subject: Re: [RFI] Cree LED Light Bulb

> On 8/11/2014 Peter Laws wrote:

>> On Mon, Aug 11, 2014 at 10:25 AM, Kim Elmore <cw_de_n5op@sbcglobal.net> 
>> wrote:
>>> That's interesting as in their on-line FAQ, Cree says they approve of 
>>> installation in can fixtures. We've had 42 W CFLs in there for the last 8 
>>> years and never seen evidence of overheating. However, the light is cycled 
>>> a lot and I suspect the failures we've seen are related to that. Cree again 
>>> states that power cycling is harmless to their LED bulb. I guess I'll get 
>>> to find out!

>> Lumens, gentlemen, please!  IMHO, bulbs should also receive a rating
>> based on how much heat they generate.  Clearly, there is a difference
>> in the heat output of an Edison bulb that consumes 60 W of power and a
>> CFL that puts out the equivalent light (at considerably less power
>> consumption).

> Actually, we know this:
> The TYPICAL 60 Watt soft white edison bulb generates 800 lumens.  Now,
> if  there  was  100% luminous efficiency, you get 683 lm/W, so you are
> getting 1.17 watts of actual light, and 58.83 watts of heat

> The cree bulb I have sitting here, which claims 75 watt equivalent and
> 800 lumens..(Interesting, eh) draws 14 watts

> Again,  you're  looking  at  1.17  watts of light, and therefore 12.83
> watts as heat

> Pretty  much,  if  you  think  about  any lightbulb, assuming it isn't
> giving  off  massive RF, or sound, anything not out the front as light
> is going to be heat

73 de KG2V - Charles Gallo
Quality Custom Machine-shop work for the radio amateur (sm)

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