The Plastic Classic Forum

Since Dave asked about this I figured I'd post my review of a few LED bulbs. The Sensibulb is the clear winner but there are some good value bulbs too...

I went ahead a acquired five different high output interior 12v LED bulbs for comparison.

I wanted to capture the actual beam width and the light color as best I could. I brought the bulbs home and set them up in my garage to shine on the back of the white garage door. I placed the test fixture 25" from the door and used a Trojan deep cycle battery at a 13.2V float stage charge to power them.

In order to capture every bulb with everything being equal I used a Nikon D-200 DSLR with a 24-70 f 2.8 lens. It was mounted on a tripod with no flash and the garage was pitch black except for the one bulb being photographed. I even re-shot each and every bulb as new ones came in the mail so they were always shot within minutes of each other and at the same level of darkness in the garage. In between shoots I also moved the fixture and camera so I wanted every bulb to be in the exact same position to be fair. The camera was set to manual mode and every picture was taken remotely and on the same exact setting, so all could be as equal as possible. The camera settings were: 1s f/10.0 at 24.0mm iso200

Please note that a camera sees color temperatures differently than the naked eye and tends to skew everything to a warmer glow. The yellow/orangy tints are actually nice and warm and the whitest bulb, the Dr. LED, is almost blue in the real world.

None of the photos, where light was captured, was post processed or run through any photo editing software. This is how they came out of the camera.

I chose these manual camera settings because it gave a clearer delineation of where the effective light spread stopped and petered into darkness.

Current Draw is as follows:

20W Halogen = 1.745 amps
10W Halogen =.87 amps
Sensibulb = .194 amps
MarineBeam 6 bulb = .158 amps
MarineBeam 10 bulb = .188 amps
Dr. LED = .138 amps
Superbrite LED = .141 amps

To put it in perspective one 10W Halogen bulb uses 4.48 times (448% more) electricity than does one Sensibulb and one 20W halogen uses 8.9 times (899% more) electricity than the Sensibulb which was the highest drawing of the LED's tested.

This is the Dr. LED G4 / MR-11 it had the narrowest beam width and the coldest bluish color. It was also the least bright with the lowest current draw at .138 amps. At $28.99 I think the MarineBeam bulb is a significantly better value and if you compare price, with beam width and light output, it can't even touch the Sensibulb:


This is the SuperBrite LED's MR-11 WHP6. It's a six SMD bulb and a decent knock off to the Marinebeam MR-11-6 below. To the naked eye looks virtually identical but the lighting & current draw tell a different story. It has a cold blueish tint and is slightly less bright than the MarineBeam MR-11-6. At $14.95 it is a decent value but certainly not the best color representation. Another clue that it is not the same exact bulb as the Marinebeam is the current draw. This bulb drew .141 amps and the Marinebeam drew .158 amps.

This is the MarineBeam G4 / MR-11-6 it uses 6 SMD LED's and had a much wider beam width than the Dr. LED and about the same as the Superbrite LED bulb but was noticeably warmer in color output. Though the Sensibulb was considerably warmer and more natural looking this was the second most natural looking and fairly close to an incandescent bulbs color. It was brighter and warmer than the Dr. LED bulb and the Superbrite LED and at $24.99 it is a lot cheaper than the Sensibulb. It's a good choice for a price conscious user & it consumes .158 amps :


This is the MarineBeam G4/MR-11-10. Like the G4/MR-11-6 it uses SMD LED's but instead of six it uses ten. It was brighter but notably colder than it's smaller sibling bulb. At $27.99 it is a lot cheaper than the Sensibulb and a good choice for a price conscious user who needs more light output than the G4/MR-11-6 type bulbs can give.. I was not impressed with the color rendering of this bulb and it is tending towards colder rather than warmer especially when compared to the other MarineBeam bulb. It consumes .188 amps :


This is the Sensibulb and it fits both horizontal and vertical fixtures it had the widest beam width, even hitting & wrapping up onto the ceiling. It also had the warmest most incandescent like light output and was definitely the brightest of the tree bulbs but also the most expensive at $39.95 ea. It was significantly brighter than the Dr. LED bulb but also drew the most current of the three LED's at .194 amps (note the reflection off the ceiling and keep in mind this bulb was only 25" from the door):


I have also included this G4 10W Halogen bulb photo for comparison. It draws .88 amps or 448% more than the Sensibulb:


Here's a G4 20W Halogen bulb it draws 1.745 amps per hour or 899% more than the Sensibulb. In terms of light output the Sensibulb falls in between the 20 watt and the 10 watt halogens..


These are the bulbs tested:

From L to R: Sensibulb, Marinebeam G4/MR-11-10, Marinebeam G4/MR-11-6, SuperBrite LED MR-11 WHP6, Doctor LED Mr-11

Front Row: 10 Watt G4 Halogen, 20 Watt G4 Halogen

Test Fixture:



P.S. If you mention to the folks at Sailors Solutions that you read about the Sensibulb here, Nick, one of the owners, has agreed to give 10% off..:D

Great test - certainly provides food for a number of cold winter evenings calculating system requirements, rather than grinding . . .

Maine Sail,

Thanks for gathering and posting the data.

I have a question that I don't know if you can answer, but it can't hurt to ask:

My (minimal) understanding of LED bulbs leads me to belive that the bulbs "lose" their whiteness (or brightness?) over time. Maybe more if they're not "blue"?

Have you done any tests, or do you have any knowlege or "gut feeling" data on that>

Thanks, Rachel

Sorry Tim I don't know what happened... Perhaps you can delete these flub ups??

Sorry duplicate post..?? No delete feature??

This can be true with cheaply built LED's as temperature is the number one enemy. Well built & regulated constant current LED's do not generally suffer from this phenomenon due to expensive circuitry that regulates voltage and keeps temps within the safe range. A bulb like the Sensibulb should last a very, very, very long time and both Marine Beam and Sensibulb estimate 50,000 hours of use. You pay more but you also get more...

Cheap LED's do not last because they are not voltage regulated and many boaters have experienced failures and been turned off by the technology. My original Sensibulb has four seasons on it and still works as good as new. I bought a couple of cheapies that failed within the first season, and they also performed like crap.....

I think you'll see the price come down and the quality go up over the next few years. Even at the current high price I still think the Sensibulb at 35.99 (with 10% discount) is a steal compared to a battery bank/alternator upgrade..

Thanks for that info.

As I was reading your post, it came to me that maybe it was something about the ... coating (?) that helps to make them white degrading. Or is this what doesn't happen if they're properly regulated?

Is the regulation something that can withstand the variations in voltage that you tend to get with boat batteries? (I suppose it must be, but while I'm asking...)

Thanks again,

Rachel

Yes the bulbs are designed to be "constant current" meaning no matter what the ship's voltage is the bulb still only sees what it's designed for. This is why the Sensibulb has that huge heat sink that controls bulb temp. As for them losing their color this was true to a point but still heat was a factor with the older style round dome type bulbs. The flat SMD type emitters don't suffer from this like the first generation bulbs did but again it was mostly caused by heat and improper design.

Prior to general lighting needs LED's had been primarily used in situations where constant current was available. LED computer monitors, auto dashboards, medical equipment etc. etc. all had constant current for the LED's. When companies first started building "cheap" LED's for the automotive industry they did not know how big a role temp compensation played until they started having lots of failures...

Good LED fixtures or bulbs are controlled by constant current circuitry. Constant current insures that LEDs within a single bulb or fixture shine with the same brightness despite the fact that each LED may have a different internal voltage requirement (called the forward voltage). Cheap LED fixtures provide a fixed voltage to the LEDs, and consequently, some LEDs in the fixture will be brighter than others. Good constant current circuitry has no problem whatsoever with the varying voltages that the boat's systems will provide it.

The majority of white LEDs are really blue LEDs with a phosphor coating that provides a white light output. This coating does degrade over time, and results in loss of brightness and a color shift, but the timeline for such a failure is years. It also happens slowly enough that most people don't notice until they replace another fixture nearby to one that is years old and see a difference.

Keep in mind that the industry standard for quality LEDs is 50,000hrs as Maine Sail points out. This is the point where the LED is only 70% as bright as when new, not the point where it fails to produce light. With good temperature regulation, 100,000hr lifetime is not unheard of.

Another advantage is that constant On/Off cycles that doom filament type lights don't have any detrimentally effect on LEDs.

I design LED light fixtures for the retail and industrial industries, and the prices on high brightness LEDs are dropping like a rock, and will continue to do so with the new advancements in manufacturing.

Maine Sail -- I have read quite a few of your test reports here and on other forums for various items, and I am always impressed at the amount of effort and attention to detail you put forth while conducting tests in a non-laboratory environment. I don't know if you are an engineer, but you certainly think like one and it shows in your reviews. Thanks.

Ryan

I'm not an engineer but did sleep at a Holiday Inn Express..??? Seriously though research is a huge part of my "real job" so I tend to take what I know about science/data etc. and translate it into boats where applicable. Glad you like what I do. This is stuff I've always done for myself (I know overkill) and I thought others could benefit from some of what I learn in each boat endeavor. I did work in boat yards when I was younger so all of this is not self taught. I'm like a sponge and have gathered lots of info over the years which I hold onto for future reference...

Thanks to both of you for the additional information. It's good to understand a bit more about how they work.

Sounds like LEDs are a little bit like electronics at the moment, in that one should not buy them too far in advance (if one is, say, working on a refit), since they are getting better and cheaper relatively quickly.

Rachel

Maine Sail,

I can't thank you enough for the thorough and illuminating (there, I said it.) review of the available LED bulbs. A perfect way to quickly determine the differences between manufacturers and their line of products. Very professional.

And I can't believe I bought the WRONG damn bulbs...

Jeez, I wish Rachel had been standing next to me at the boat show and whispering her sage advice about holding off purchasing during a refit.

Cheers. I think.
Dave

Excellent article, thank you, very informative. I was looking at the $39 bulbs and to refit KAHOLEE's interior alone would be in the nature of $440, or around $400 with the 10% discount. Tempting, but...

What is the life span on these units?

50,000 hours+++ or a lot more than you'll ever use them...

You have to watch those hour ratings. They are generally based on continuous use. It's the on/off cycle that really reduces the life of a light, or circuit, due to the corresponding electrical surge.

In any event, I have now switched to Sensabulbs in all my interior lights. Their circuit is designed to prevent excessive heating which is reported to be the real killer of LEDs so I am looking forward to a long and electrically frugal life for my new lights. I have an entry on KAHOLEE's website describing the installation with pictures.

FWIW, the on/off cycles do not have any appreciable effect on LED lifetime as it does with filament or arc type light sources. In fact, the preferred method of dimming LED light sources is via pulse width modulation, which is essentially turning the LED on and off faster than the eye can see

It's not so much the LED itself I'd be concerned about, but the circuit feeding it. According to the manufacturer it's heat that is the enemy of the LED and the attached circuit and heat sink are designed to limit the heat buildup, even shutting the LED down if heat exceeds some preset point.