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Mike M
04-05-2008, 10:28 AM
I wired 9v batteries to (2) LED's by DGLIGHTS, the Palm65, and the bigger one (can't remember name, but is 35 watt equiv.).

They both had what appeared to be full power for an hour or so, then the bigger one started diminishing (by eyesight, I wish I had instruments). The smaller LED seemed in full power for another hour or so.

I started two days ago, and they are both still on, but significantly faded. I was under the impression they would not fade when voltage dropped below requirement, instead they should go out or start blinking. But they both faded.

The main purpose of this was to test usability of battery powered fixtures for demo's. I did a demo set up the other day which was double my usual time (6 hours, not including presentation/consultation).

My next test will be around my own property, placing these portable lights, and turning my halogens on and off to compare similarities in effects, including beam spreads, apparent color temp, and intensity. If they are close, I will probably use a combination of transformers and these LED portables, to reduce my set ups by 1/2 the time, minimum.

A good test will also be palmetto trees and other tropicals at my neighbors'.

Pro-Scapes
04-05-2008, 12:41 PM
I think you would be better off with something with more reserve than a small 9v battery. Even with LED's you could use the capacity of a larger battery
Even something like a 12v airsoft battery. With the tamayia style connectors you could rig it up so 1 pack could run 4-5 lights like a small hub and use leads.

Better yet you could mount the batteries in a small enclosure and have the fixture mounted to it with an on off switch so you could plug it in and charge it rather quickly. This would afford you to do all night demos without a problem and probably even multiple day demos on a single charge.

Really what I would do is get some 75w transformers and 16ga leads and install tamaiya type connectors in the wire. Just string it along. This would be your cheapest and most effective route and VERY easy to set up. Simply plug the fixtures in along your line

http://cgi.ebay.com/12V-4200mAh-NiMH-Battery-Pack-for-AIRSOFT-Gun-DC-Power_W0QQitemZ260225877902QQihZ016QQcategoryZ40975QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

INTEGRA Bespoke Lighting
04-05-2008, 04:17 PM
Billy, great minds think alike.

Mike, a 9v akaline cell simply does not have enough reserve capacity to power those LED fixtures properly. Moving to a hoby NiMh cell like Billy pointed to, or even a small 12v utility lead acid tractor battery would solve this for you... for demo's that is.

My son and I are into high end R/C boats and Nitro R/C trucks. The 4700mAH NiMh cells that we use are phenomenal units. They recharge (with a smart charger) very quickly and have massive reserves for their size. The ones I have here are all 7.2 - 8.4 Volts... but I am sure you can find some at 12V too. A bit pricy retail, but ebay always has some great deals from SE Asian sources.

http://stores.ebay.ca/All-Battery-Center_RC-Car-Battery_4-8V-7-2V_W0QQcolZ4QQdirZ1QQfsubZ12793743QQftidZ2QQtZkm

Quick connectors are a great idea too.

Have a great day.

Pro-Scapes
04-05-2008, 04:34 PM
My son and I are into high end R/C boats and Nitro R/C trucks. [url]

Have a great day.

Guess you have not seen my 48" 55mph gasoline enforcer(6hp@17,500 rpm) or my 30 inch brushless powered that hits 65

Nitro is a pita. Go gas or go home.

back on subject. if you go with 7.2v packs your going to have issues. You could always get loose cells with tabs on them and configure your packs in just about any format you would like. I would go with the 12v packs prebuilt.Find some little plastic boxes to hold them. Drill in an on off switch and then glue a 1/2" threaded pvc fitting on to the top. The wieght of the battery would hold the light in place.

The more I think about it the more I see a good point in just doing some small plastic tool boxes. Battery inside. Open the top and have 5-6 lead wires (18ga?????) with quick connects. Run the wires out and the storage box becomes your hub. You could even mount a photocell on the storage box to leave it for multiple days.

INTEGRA Bespoke Lighting
04-05-2008, 04:40 PM
Billy, you have a gas boat? I bought Jack the Traxxas Villian EX last year as our fist forray into RC boats. (I figured at 6, electric was the way to go for him.) I have been looking around for a gas boat for myself... not sure which way to go. I know I dont want the issues of a nitro on the water, its enough of a pain in the arse on the 4x4 TMaxx we have.

Any direction on where to find a great RTR gas boat?

Mike M
04-05-2008, 04:45 PM
Okay.

I'll get little hobby gas-powered generators built into the housings and my set will be a dozen gas-powered lights.

A little loud and heavy, but really cool.

Actually, fyi, I already got the 75 watt transformer for the LED's, but have yet to make a big run with lots of plug-in points for leads.

I bought a bunch of the Anderson "power-poles" for quick connects. They are available on-line at hobby sites. I'll check out the battery selections. I thought of that, too, but very expensive.

Pro-Scapes
04-05-2008, 04:46 PM
Billy, you have a gas boat? I bought Jack the Traxxas Villian EX last year as our fist forray into RC boats. (I figured at 6, electric was the way to go for him.) I have been looking around for a gas boat for myself... not sure which way to go. I know I dont want the issues of a nitro on the water, its enough of a pain in the arse on the 4x4 TMaxx we have.

Any direction on where to find a great RTR gas boat?

www.whobbies.com Tony Castronovo is the best. He invented gas boating i think. I see now the super G kit is only 550. When I got mine they were a grand. That will give you 40 plus mph .. I had tony build me a 6hp mod motor altho most the time I preffer the stocker as its less picky.

45 min run times and you can run allll day long for 3 bucks in 2 stroke gas.

If you want exotic you better bring your visa. A Bonsi can run upwards of 8k for a twin inline http://bonzisports.com/

David Gretzmier
04-07-2008, 12:10 AM
you can buy rechargable "sub-c" cells( the same cells that run better cordless drills/tools) that are around 4500 mah, use nimh ( stay away from lithium, hot and explosive when building bundles) and build you some 12 volt packs with 10 cells. they run about a buck apiece on battery websites and you can buy them in 100 packs. buy the ones with tabs on the top and bottom and they solder together pretty easy. the photo-cell idea is interesting, but may cause you issues when you do demo's right before dark. you could rig a charger from a cheap 12 volt drill charger at harbor freight.

I have thought about this same setup using the mr-16 warm whites with the 3cree led's in each mr-16. It really is close to lumens of a 20 watt mr-16, and since demo's usually only run 30 minutes run time, maybe the heat issue won't be a big deal.

INTEGRA Bespoke Lighting
04-07-2008, 01:06 AM
[QUOTEI have thought about this same setup using the mr-16 warm whites with the 3cree led's in each mr-16. It really is close to lumens of a 20 watt mr-16, and since demo's usually only run 30 minutes run time, maybe the heat issue won't be a big deal.[/QUOTE]

David: If you wan to see an MR16 LED lamp that will make you smile, then fire me off an email. I will then register you and send you off a info kit on a new lamp I have found.

Regards.

TPnTX
12-28-2010, 10:44 AM
I've been wanting to get a bike light for cross country night rides. The ones on the market are either for you to be seen as in road bikes or really expensive used to totally light up a trail. 500-900 lumens. 200.00+

they all use 7.2 lithium packs. What I'm trying to figure out is an LED light that is ultra bright and is 6v?

I think it would be cool If I could DIY a light that would be really bright, have a wide spread, last for about 2 hours and do it on the cheap and of course not be real heavy.

I know you can get those Lithium batteries that look like AA. So a battery pack should be pretty easy.

anything to do with biking is automatically jacked up in price. I don't need all the logic and controls. I just want on/off bright light. I immediately thought of you guys for info or wild ideas. It's not like I don't have the money its just that I hate spending it :)

steveparrott
12-28-2010, 11:52 AM
you can buy rechargable "sub-c" cells

I've heard that some rechargeable batteries will fry an LED - something to do with differences in resistance and/or impedance. Anyone know more about this?

lilmarvin4064
01-12-2011, 02:59 PM
I've been wanting to get a bike light for cross country night rides. The ones on the market are either for you to be seen as in road bikes or really expensive used to totally light up a trail. 500-900 lumens. 200.00+

they all use 7.2 lithium packs. What I'm trying to figure out is an LED light that is ultra bright and is 6v?

I think it would be cool If I could DIY a light that would be really bright, have a wide spread, last for about 2 hours and do it on the cheap and of course not be real heavy.

I know you can get those Lithium batteries that look like AA. So a battery pack should be pretty easy.

anything to do with biking is automatically jacked up in price. I don't need all the logic and controls. I just want on/off bright light. I immediately thought of you guys for info or wild ideas. It's not like I don't have the money its just that I hate spending it :)

This one looks really good for the price...

http://www.dealextreme.com/details.dx/sku.36018

and there are others. http://www.dealextreme.com/products.dx/category.905~page.1~pagesize.52~pagesort.relevence

You could DIY one of course, if you wanted it to run on 6V. Depending on the LED / LED configuration, you would just need to use a boost driver (or buck driver). http://ledsupply.com/led-drivers.php

Also those of you that don't like the dangers of using lithium-ion batteries should take a look into lithium iron phosphate cells (LiFePO4). I have some Headway cells that are pretty awesome.

jmiller@kichler.com
01-12-2011, 05:52 PM
Obviously I can not answer for another manufacturer. But when you say you thought that when the voltage went down to a certain level the lights would not simply fade, but flicker, that depends on the manufacturer and the electronic drivers they use.

Many LED lighting manufacturers out there today do not control the current to their LEDS. Although you can be saving energy by using LEDS, the fixtures may be running with the same characteristics of an incandescent lamp. They will dim under 12 volts and they will burn out quicker over 12 volts.