LED bulb choices

[MilesAndSmiles]

I'm preparing to switch from the factory bulbs to LED lights in my RV fixtures. I've noticed that some people replace the bulbs in their overhead clamshell fixtures with an LED bulb of similar size and shape. Others have used an adapter and replaced the bulb with a square plate-shaped array.

 

Can anyone help me understand the benefits of going one way or the other?

 

Thanks!

[oldjohnt]

Dunellen, I apologize, I don't have time now to list all the specific part numbers and units I've used along with a lot of detailed information, but for an initial short n sweet response here is my experience.

 1) NONE of the direct plug in fit round BULBS (even with multiple LED's) I tried in my clamshells produced as much 'light" (see Footcandle formula below) as the flat square multiple LED panels similar to those linked below. The units linked below are also available with adapters to fit the old style bayonet base or the small T-10 marker light units as shown in the link. 

http://www.ebay.com/itm/261959559713?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

2) NONE of the flat adapter panel type LED's above and NONE of the LED round bulbs in my old clamshells produced as much "light" as when I purchased totally new LED clamshell twin fixtures  (I will find and post that link later, MUCH brighter then just replacing "bulbs" even flat panel types) SUBJECT TO THE FIXTURE OF COURSE

3) Its the LUMENS (and net Footcandles) and the Kelvin Degree of color that really matters BUT ITS HARD TO SEE THOSE SPECS WHEN YOU SHOP ON E BAY OR AMAZON grrrrrrrrr. A "real" LED supplier may well have that important data available.  

All I have to offer now, I will add to this later.

PS  "Footcandles" of light is Lumens X Coefficient of Utilization (CU) per unit area. One reason the flat panel type can produce more footcandles (what you really need) is simply they have a much higher CU then say a round bulb which has LED's top n bottom in which configuration the light produced by the top LED's has to be reflected back down. The flat panels direct the light straight down where its needed absent inefficient reflection.

SUMMARY if you don't want to replace the entire fixture, Id go with the multiple LED flat arrays as all the ones I tried produced more "light" then any direct fit in bulbs I tried.   YOU HAVE TO KNOW THE TOTAL LUMEN OUTPUT AND COLOR !!!!!!   ONLY then you can compare apples to apples

NOTE these are ONLY my experiences, others may well have total different experiences as so much depends on Lumens and CU and fixture design, but the flat panel in general proved superior in MY applications. 

John T   Too long retired EE and NO Expert, so do as the "experts" tell you.

 

 

 

[Kirk W]

I have done this using the led arrays that have the proper base for the lights which came in our RV and the reason is that it means I don't need to buy a bunch of new fixtures. In most cases, there is more than one size of led array for any given light socket and one benefit of conversion is that you can use a much higher lumen rated led where an incandescent once was and not have the overheating problems a higher wattage rated incandescent would cause. 

For example, under the cabinets over our kitchen stove & sink I put as large an array as would fit and Pam loves it. I did the same thing above the bed where we sometimes read. In the overhead lights that light the center of our RV I used the smaller arrays that were similar in lumens to the original incandescent bulbs. Keep in mind that an led uses far less power, meaning fewer amps because they make more of the energy used into light with very little of it dissipating as heat, which is the major waste of power with an incandescent bulb. As a result, you have bulb size (lumens) choices with an led that you do not have with the old incandescent bulbs. 

[kinseypw]

You can get flat "pancake" type bulbs that plug in directly and they are available with a lumen output equivalent to flat panels. The panels come with double sided tape to hold them to the top of the fixture and it can become unstuck. Not a problem for light, just looks odd. You can find suppliers on ebay that specify lumen output - you want over 200 to match typical bulbs and you want a color temp about 4000k to match warm white incandescent bulb light.