So I’ve bedazzled the interior of the van with a mile o’ LED strips, how much power do they draw?
strip over kitchen area = 0.37 A, 4.7 W
strip over sliding door = 0.39 A, 4.8 W
strip over lower bunk = 0.30 A, 3.1 W
pop top perimeter strip = 1.43 A, 17.6 W
total = 2.47 A, 30.2 W
(funny, power values differ slightly than what I posted back in Feb when I installed the strips over the kitchen and the sliding door. Due to the different controllers?)
With the PWM brightness controllers, the power consumption does go down when lights are dimmed.
For comparison, the stock fluorescent light above the sink found in some westies draws 0.9 A and 8 W. I don’t know what the power draw is with the stock light and incandescent bulbs.
Update: David and I were discussing (in the comments) white LED spectrum. He sent me the pdf file about that subject that is buried somewhere in the Cree website.
#1 by oldfussbudget on July 4, 2013 - 1:08 pm
Our ’84 had the single-halogen fixture with a clear plastic lens that looked a bit like cut glass, all tetrahedrons or summat. It had a GE lamp rated 25 watts. Gave plenty of hard, dazzling light. We didn’t use it much but one time the lens distorted anyway. What we normally used was a 7 watt CFL in PAR narrow-flood format, hung up in the rigging in a bendy clip-on fixture. Running from an inverter, of course.
#2 by albell on July 4, 2013 - 4:57 pm
I think I might have one of the old halogen lights somewhere in my stash. I’ll see if I can get a wattage off the bulb.
I replaced it early on with a fluorescent unit which was close to same size. That one cast a morgue-like light.
#3 by oldfussbudget on July 4, 2013 - 6:59 pm
My halogen was definitely 25 watts. I had to source a spare lamp for it which cost a small fortune, and then we probably put an hour on it in ten years. The PAR lamp was great, gave plenty of light where you pointed it and got all soft around the edges, never a glare problem. We’d mostly clip it to the skylight mechanism IIRC. Drew an amp or less with a small fanless inverter.
My brother is shifting his 36′ land yacht from strip fluorescents and halogens to LED strips inside the fluorescent fixtures and lamps installed in the halogen fixtures. He’s saving considerable amps. His wire runs are something like 150 feet!
#4 by albell on July 4, 2013 - 7:12 pm
Ok, 25W for the old halogen. Boy things have changed eh? I can get a butt load (yes, a yet to be approved term for quantity of light) of light from the LEDs for 5W more.
No prize for guessing I am a fan of LEDs. The colour value/quality is now very much comparable to halogen. It probably will improve, I think there might still be holes in the output spectrum. But the current (ha!) state is pretty darn acceptable.
Now, if they will only do more work on MR16 and MR11 LED “bulbs”, increasing the lumens and dropping the price, people can swap out a lot of track light bulbs.
#5 by oldfussbudget on July 4, 2013 - 7:23 pm
You could say that there are holes in the output spectrum, since it only has two colors in it. White LEDs are really blue LEDs with an overcoat of yellow phosphor, and the combination of blue and yellow in correct proportion we perceive as white. The blue has a sharper peak than the yelloow, but neither one is what you’d call broad spectrum. I had to read up on this some months ago and now I understand how the CCITT color diagram works. Cree has a good writeup on this buried in their document library somewhere. It’s the appendix to a document on how you can get cheaper results in multi-LED fixtures by buying a mixture of color bins and mixing them appropriately instead of paying the big bucks for ones all of the specific color temperature you want to end up with.
#6 by albell on July 4, 2013 - 7:56 pm
Thanks David, I’ll look up the Cree doc.
Originally I had the idea of using RGB (the 3 elements in one tight unit) strips and trying to mix colours to get the warm light I wanted. I still might do that someday, but the strips I have now are pretty acceptable. But think of it, if you could mix. I think (but not sure) that some stage lighting is mixable LEDs.
#7 by oldfussbudget on July 4, 2013 - 8:01 pm
Their site is a bugger, though interesting. I”ll send it to you.
#8 by oldfussbudget on July 5, 2013 - 5:37 pm
The trouble with the blue/yellow white LEDs is Color Rendering Index. You’re much more likely to find things, especially red things, look different than they do under incandescent light (than you would with an RGB mix to get the same effect), notwithstanding that the two lights appear the same color to you when you look at them.
#9 by albell on July 5, 2013 - 6:45 pm
I agree. Perhaps this might come up when taking a pic in that light. I’ll be camping this weekend, so perhaps I’ll take pics of something red in daylight, then again in LED light.
#10 by albell on July 4, 2013 - 8:04 pm
I tried, you are right, the site is a bugger. Wikipedia article interesting though
#11 by Joel on July 4, 2013 - 9:30 pm
So Mr. Shooftie have you played much with solar charging yet? I’m looking at the flexible roll vs the portable “ZAPP’ hard unit. Flexible about 40 watts, ZAPP 80 w, 5.0 amps
#12 by albell on July 4, 2013 - 10:50 pm
no I haven’t. And I’ll tell you why. The sun don’t shine much up here 🙂
But it I were to get one I’d go for the 80W hard unit. I don’t know much about solar cells but I do know that the flexible ones are not as efficient and less bang for the buck compared to the rigid type. And amongst he rigid type, the amorphous cells less efficiaent than the crystalline types. Jeez, now I’m really talking out of my ….
But back to firmer ground, I think scribbling down and energy budget would help. Try and estimate (or even measure during a trip) how much juice you use per day etc.
#13 by famillysyncro on July 5, 2013 - 4:48 am
Where is the night picture of the van to see how nice it is looking?
Almost 18W for the pop top perimeter. How long is that one? 4 meters?
#14 by albell on July 5, 2013 - 7:04 am
I’ll get a pic when we go camping, which I think will be this weekend. I think it is about 4.8 metres in total for the sides of the pop top, can’t recall the end measurements.
#15 by Joel on July 5, 2013 - 10:47 am
Thanks, absolutely right about getting the budget together. I’m thinking the same. Have I said you have a Great blog today? You have a Great blog.
#16 by albell on July 5, 2013 - 10:53 am
I’ve only done a back of the envelope type budget calc. I should do a better one based on some real measurements (the Doc Wattson meter should help that, it will record A/hrs, kW/hrs). Myabe will do it this weekedn as we are heading out to do some more clearcut exploring. I just have to remember to re-set the meter before we start.
I hope the blog gives folk some ideas and also warnings what not to do. I really appreciate the comments and I do welcome suggestions.
#17 by albell on July 8, 2013 - 1:23 pm
I took note of power usage this last weekend, from 4 pm when we set up camp, to 2 pm next day when we broke it 🙂
7.2 A hrs, 0.08 kWhr, 3.12 peak Amps.
So this was with the radio playing from about 5 pm to 10 pm, then about 2 hours the next day ( as we are good liberals, was set low, even though no one was around, and to the nearest NPR station – Port Angeles :)). Not all of the LED lights were on, but lights on for about one hour. Water pump used a little, fridge cooling fan did not come on at that time.