led style...?

RoyBell wrote:
I would like to change my lights out to LED. One switch runs 5 lights at once. That's 200 watts @ 12 volts. If my math is correct, that is 16 amps. I can really hear the inverter buzzing away when the lights are on. When I turn them off, it gets quiet again. Anyone not like the LED and switch back?

I have heard of people who didn't like the blue color of their LEDs and put their incandescent bulbs back in. Also, I have heard of people who bought LED lights with regulators and couldn't stand the radio interference (RFI) that the regulators produced. IMHO, they bought the wrong LEDs and were too impatient to figure out what are the right LEDs for them.

I switched to LEDs about 3 years ago and would never switch back.

Buy one or two and try them out before buying a lot of them.

I would like to change my lights out to LED. One switch runs 5 lights at once. That's 200 watts @ 12 volts. If my math is correct, that is 16 amps. I can really hear the inverter buzzing away when the lights are on. When I turn them off, it gets quiet again. Anyone not like the LED and switch back?

Here is the final word on the meaning of COB. :B

I just wanted people to not be confused- COB is the newest technology*- here's an inforgraphic with key differences:


As to what the styles are called- you can call them anything- omni directional vs uni directional, flat panel vs bulb style, etc. They just are not COB LEDs, though you can get 'corn cob' style in a true COB- here's one with COB on the side, and an SMD on the end:




* I should add- as of ~noon, 5/7/2015 - tomorrow may be different :)

Original poster here.
Thanks for the info and discussion. Good stuff.

apology:
(I didn't mean it to go the way of a semantics argument... ie,"cob.")

Lots of numbers and confusion. I have always just called the style either, cob (as in corn cob) or pancake, (as in flat and round like a pancake.)

Anymore ideas or experience greatly appreciated.

I have always understood COB as meaning it looks like a corn cob. To me, your definition of COB is more like SMD which stands for Surface Mount Diode.

Many people seem to think SMD stands for a certain type of LED, like a 3528 for example, while it actually defines the package and the type of mounting to the Board.

Thanks guys for helping me with LED terminology and tech info.

With the old-style LED "bulbs" through trial-and-error I found that 2.7 WATTS is about the maximum a lamp can consume and balance thermal emissions through whatever matrix is used in the RV bulb replacement industry.

To increase above 2.5 watts means increasing the size of the matrix (won't fit the hole or fixture) or utilize an aluminum heat-sink. I clamped 2 three watt Bridgelux LEDs to a 2 X 3" 1/4" heat sink with 8 fin count. Applied 8.2 vdc the max OEM milliamps recommended. Set.the critter into one of the vacated fixture holes in my bus. Turned it on for 20 min.

OUCH! I could not measure instant temp but that fixture got way too hot for my liking. I'll bet my fingers suffered 200+ degrees F. My hopes of burying a thermocouple and continuing the "experiment" were dashed.

The bus overhead is encased in closed cell foam so the heat sink had little opportunity to shed BTUs.

Providing brighter lamps is going to be a challenge for the industry. BTW the power supply for the Bridgelux LEDs was divorced from the fixture. Open air.

Chris Bryant wrote:
I think people are misunderstanding the term COB- it stands for Chip On Board- a type of LED. It doesn't refer to the style of lamp- specifically looking like a corn cob.

From planet LED:

Planet LED wrote:
In COB lighting, single LED chips are placed directly on a circuit board (or substrate) which has thermal properties to disperse heat. Heat dissipation is a very important aspect of LED lighting because it can have a major impact on the life expectancy of the luminaire. Traditional LED chips are not placed directly on the substrate and therefore there is greater thermal resistance.

OK what words would be proper to describe the style of two items pictured in the OP?

Chris Bryant wrote:
I think people are misunderstanding the term COB- it stands for Chip On Board- a type of LED. It doesn't refer to the style of lamp- specifically looking like a corn cob.

From planet LED:

Planet LED wrote:
In COB lighting, single LED chips are placed directly on a circuit board (or substrate) which has thermal properties to disperse heat. Heat dissipation is a very important aspect of LED lighting because it can have a major impact on the life expectancy of the luminaire. Traditional LED chips are not placed directly on the substrate and therefore there is greater thermal resistance.

Unfortunately Chris, your correction will fall on mostly deaf ears as you'll see this misunderstanding of what a COB LED bulb is repeated endlessly on these forums. :S I've been using 16 of these non-COB LED bulbs, each consisting of 24 5050SMD chips, for a year now with no failures at all, no RFI disruption of the radio, bright with a rated colour temperature of 3200K, in fact no complaints at all from me.



Sourced at a reasonable price from this offshore vendor ... and while certainly not the latest & greatest in terms of LED construction have worked just fine for me. :B

I think people are misunderstanding the term COB- it stands for Chip On Board- a type of LED. It doesn't refer to the style of lamp- specifically looking like a corn cob.

From planet LED:

Planet LED wrote:
In COB lighting, single LED chips are placed directly on a circuit board (or substrate) which has thermal properties to disperse heat. Heat dissipation is a very important aspect of LED lighting because it can have a major impact on the life expectancy of the luminaire. Traditional LED chips are not placed directly on the substrate and therefore there is greater thermal resistance.