Wednesday, July 02, 2008

It's confirmed.......I am a nerd.

Want to know how much of a geek I am? Here is what I’ve been doing on a Wednesday night while on vacation. So I want to swap all my lights out to LED so I can take it as easy as possible on the batteries. It’s an easy formula, Amps = Watts/Volts. My battery bank is around 530 Amps. My battery voltage is 12 volt and is relatively constant. So, if you take your average 20 watt halogen light it burns 1.67 amps/hour. I also had a few 50w bulbs that burn 4.17 amps/hour. With a total of 7 of these fixtures this type of amperage draw really adds up.

Your average LED bulb will run around 1 – 5 watts or the equivalent of ~.3 amps/hour. That’s a big savings. The only problem is finding a good LED light that puts out anything even approaching the output of a 20w or 50w bulb. For a long time I didn’t think they existed. After a few bum LED bulbs I stumbled onto a small business run by a cruiser who specialized in these bulbs. He sent me a few to play with, actually I bought them to play with, and the results are below. I am not naming the company because there is one bulb in particular I’d like to use all over my boat. Sponsorship anyone?

Ok, so to get some thing approaching an unbiased, uncorrupted, analytical result I used my new camera. I plugged in a standard 20w bulb in one of my fixtures and found the settings that would yield the best possible picture. Now admittedly, this is somewhat biased because I chose to use the 20w as the control, but hey, I had to start somewhere. Anyway, after a few test shots I ended up with an f-stop of 16, 8 second shutter time, and ISO 800. That might mean something to you photogs. For the rest of us it just means I didn’t change the camera settings for any of the following pics.

This is the control with the 20w.








Here is a picture of the 50w. Somewhat brighter, but hardly worth it for the extra 2.5 amps/hour. Not to mention the fixture actually started smoking since it hadn’t had the 50w bulb in it before. These things will melt your face off.





Now the real telling photo. I bought this little gem, an 18 LED cluster, off of ebay and got two for $10. They were supposed to be equivalent to a 20w bulb, but as you can tell, it’s hardly visible at all. Junk.



I am impressed with this bulb. It has nine of the Surface Mounted (SMD) LED lights and is still a warm yellow, but not so much as some others. It’s not the same as the 20w, but for 2 watts or 0.17 amps/hour it’s a real winner. I’ll just plug two of them in.





Finally, I had high hopes for this bulb, but it let me down. It is a 33 LED cluster, but it is so yellow that the light just seems dirty. It was also the most expensive bulb in the lot at ~$50 USD. The other draw back is that it is so heavy it works itself out of the fixture and falls if not very well secured. Fortunately this one never hit the ground.




So from left to right you have the 50w Xenon, 20w Xenon, 18 LED cluster, 9 SMD LED cluster, and the 33 LED cluster. Anyone else want to buy the 9 SMD LED cluster? Let me get my sponsorship request letter back to the business owner and see what we can do. They’ve been extremely patient with all my question and have shipped the orders right out. Good people to work with. I’ll keep you posted.

4 comments:

Unknown said...

But the question remains unanswered ...

... how many blondes does it take to screw in a lightbulb?

Anonymous said...

Uhmm, I am embarassed for you. And I am embarassed because my husband found this both entertaining and informative... has referenced it twice in casual conversation...

Lee Winters said...

Your husband must be both a genious in terms of his technical understanding and extremely well read considering he looks to this blog for information. We'd probably get along.

Anonymous said...

That, or he's a nerd too, and he visits the blog to a) make sure you haven't lost your dingy, and b) see if you're on your way into town and will most likely be in need of a place to stay.