Led power draw from battery?

robertglines1 · December 18, 2011, 03:54:59 PM

I have installed Led 12 volt lighting in the bus. If I were to hook the system up to the start batt. Which are 3 series 31's regular wet cell . How long could I run them without being concerned? Total wattage is 138 watt @ 12 volts if they were all on. Assuming full charge in a perfect world. I really don't understand all I need to know about battery storage capacity. Bob With bus not running.

gulfyankee · December 18, 2011, 05:01:18 PM

I'm not familiar with the Group 31 batteries, but keep in mind that the load of your LED's at 138 watts, is approximately equal to leaving your headlights on. I would highly suggest purchasing a set of gold cart 6V batteries, at least 2. They are available at Sams Club for $175 a pair. I have been camping at my property for the last month and a half, and now have 4 of these batteries. We can go a full day doing everything that we would usually do. Using lights, watching movies, using the water pump. Wattage draw is from 50 to 200 watts, depending. If you have a toad, or at least a generator, something to be able to jumpstart your bus, then experiment. Otherwise, get a set of dedicated house batteries.

robertglines1 · December 18, 2011, 05:18:57 PM

Good comparison--as to headlights. Slapped back of own head. 3ea 31 would prob = about 6 standard auto batt so that gives me some idea. I have all kinds of duplicate systems. Looks like a few hrs in the evening would be no big thing. Prob only use less than 1/2 of wattage at any one given time. I use a 10 amp per batt maintainer when on shore power. The decision I need to make now is to run the led straight from coach batt system with maintainer. or to run 120 volt to 12 volt dc transformer to power led lights. leaning toward using coach 12 volt system. Transformer is just one more appliance to keep up.Plus I have already fried one. Bob

wg4t50 · December 18, 2011, 06:35:21 PM

Provided they actually draw the 138 watts, would mean they draw 11.5 amps. From my experience 11.5 amp worth of LED light would be extremely bright, maybe painful.
I converted all my interior lights from the halogen to LED, as they draw way less then half the current and are actually brighter, plus not the heat issue.
Guessing 138 watts of LED lites would be for a light show or what?

Busted Knuckle · December 18, 2011, 06:56:53 PM

Quote from: wg4t50
Guessing 138 watts of LED lites would be for a light show or what?

Nope no show, Bob just has plenty of light!

BK

robertglines1 · December 18, 2011, 06:59:46 PM

The 138 would be if every possible light was on. There is more than 80 ft of led strip lighting (3000 range 160 lumes) that would be dimmed and allot of under and in cabinet lighting plus bay and exterior lighting. Bob

Jeremy · December 19, 2011, 02:19:11 AM

138 watts struck me as sounding like a huge amount too, but it's probably correct for that amount of led strip. Worth bearing in mind as well that dimming the LEDs won't necessarily reduce the power consumption

Jeremy

chev49 · December 19, 2011, 02:44:28 AM

very bright me thinks. I would think that a dozen would be enough, given that i bought a bunch of the 3 watt ones from china last year, and they are quite bright.

robertglines1 · December 19, 2011, 05:29:24 AM

BRIGHT it is not you can dim bright but can't increase from to dim bought strip @300 led per 16ft instead of 600 and light glow @ 3000 instead of 5000 or 6000. 160 lumen is about equivalent of 30 watt light bulb. conclusion a little over done but with the dimer control to reduce. Remember this is for the entire coach! Is much less than 1 each 100 watt light bulbs@120 volts/.or 1 each headlight 65watt@12 volt (considering only 1/2 of these lights could be in use at any one time). Plus I like it and they put out no heat and are easy to work with. Guess the last sentence says it all. Bob

gulfyankee · December 19, 2011, 05:51:05 AM

I intend to hit lowes and walmart the day after christmas and buy the led light strings for my bus. Have one 50 bulb string outside right now for a porch light, gives off good light and only uses 4 warts.

TomC · December 19, 2011, 08:34:33 AM

138 watts of LED is a huge amount of light. There are some new LED street lights by me that use 72 LED's in them, and currently a 1 watt LED is pretty big. So basically that street light uses 72 watts (which is pretty good compared to the 250 watt sodium lights) Good Luck, TomC

Jeremy · December 19, 2011, 09:25:19 AM

Yes, we all agree, 138 watts sounds like an awful lot of light - but if you actually check the rating of LED strip, that wattage is about right for the length of strip quoted. Maybe it's horribly inefficient or the spec is being misquoted somehow - but, on the face of it, the 138 watts figure is probably correct.

Jeremy

Mex-Busnut · December 20, 2011, 02:37:02 PM

Most honorable Mister Robert sir:

I have sure learned a ton from your previous posts! In a couple of weeks, I shall be posting my new mini-split A/C install photos, which are your fault!

In case you missed it, I posted before a link to this guy that I learned a whole lot from, about batteries, chargers, solar, etc. It is certainly NOT a quick read, but I believe well worth your time. By using correct charging techniques, he is getting 8-10 years out of his battery life! And he boondocks in the snow for weeks! Check it out.

[url=http://handybobsolar.wordpress.com/the-rv-battery-charging-puzzle-2/]http://handybobsolar.wordpress.com/the-rv-battery-charging-puzzle-2/]
[url]http://handybobsolar.wordpress.com/the-rv-battery-charging-puzzle-2/]http://handybobsolar.wordpress.com/the-rv-battery-charging-puzzle-2/]http://handybobsolar.wordpress.com/the-rv-battery-charging-puzzle-2/]
[url]http://handybobsolar.wordpress.com/the-rv-battery-charging-puzzle-2/[/url]

Blessings to all for 2012!

rv_safetyman · December 20, 2011, 04:20:33 PM

Dr Steve, for some reason I have that site on my browser trying to make my way through all of his minutia (and you guys though I was bad). It is a very hard blog to read. I think buried in his stuff is some good information.

It would be fun to have Sean's opinion of his information.

I think we are off the subject a bit, but it is somewhat related.

Jim

Oonrahnjay · December 20, 2011, 06:00:57 PM

Quote from: rv_safetyman on December 20, 2011, 04:20:33 PM(snip) It would be fun to have Sean's opinion of his information.

I'm very interested in his info, too. He seems to encourage really cranking up the charging voltage. If his way means really "boiling the batteries" to get that last couple of %-age of charge, I think I'd be inclined to accept 94-95% charged batteries at a slightly lower voltage (would a slightly lower voltage be "safer". But I'm very inexperienced with this and it will be good to hear what genuinely knowledgeable people think.