Electronics, Lighting, & Gadgets - would dual lights=double the light?

Ok, so there is a ton of useful info in the stickies of this category, but they have waaaaay to many postings to go through. My question is simple. If I was to put three 1 watt led lights on my bike, would I get the same amount of light as a single 3 watt light? If I already had a headlight rated at 40 lumens, added another one, would that be 80 lumens?

If I was to put three 1 watt led lights on my bike, would I get the same amount of light as a single 3 watt light?

That would depend on the efficiency of the LEDs at that power level.

3 LEDs with 1W put into each might not be working so hard and therefore be more efficient.

A similar LED with 3W going in will be working harder and will be less efficiency, you might get a few more lumens at the cost of buying more LEDs.

How are you planning to power these LEDs ?


If I already had a headlight rated at 40 lumens, added another one, would that be 80 lumens?

Yes.

not really.
It's not simply about adding up all the output.
There's more to it, like beam pattern, is it wide? is it narrow? flooder? thrower? spill?
Where is it pointed? all on one spot? spread out?
etc. etc.

IMO the best part of running two lights. Especially if you do the handlebar/helmet combo is that it helps take the harshness out of the shadows. With just a single light, especially on the bars, some of those little dips look like huge potholes because of the single light source.
My 3w helmet light is currently broken and I'm using a little one watt LED handlebar light (I usually just left it on strobe all the time before as an attention getter) for my main illumination right now until I set myself up with something else. It works well enough but wow the shadows hide stuff. I was considering milling a custom helmet-mount housing for a P7 LED on a small ball pivot with a remote battery box to reduce the weight on my head and have a more integrated look but I'll probably loose enthusiasm for that before I get started on it and just buy one of those little super lights off DealExtremez and rubber-band and zip tie it.

OK, maybe my question wasn't so simple. LOL
I am just trying to figure out what light system I am going to get. I have a couple large multiple led lights like this:

http://www.dealextreme.com/details.dx/sku.2933

I used those on my upright. I am now in the process of building a coroplast velomobile (which is a full body fairing on my tadpole) I am hoping to get a light that will go on the inside of the nose of the fairing that can be turned on by a switch wired in the cockpit. If I wasn't able to do that. The smaller the light, the better to keep aerodynamics up. So, I was thinking about getting three of these:


http://www.dealextreme.com/details.dx/sku.18307

Why not just get one 3W led that puts out 200+ lumens?
Plenty of the DX lights are rated around that point.
More aerodynamic and brighter than three 1W 50lm lights.

try some Q5-WC lights which have 2xAA options.
something like this http://www.dealextreme.com/details.dx/sku.14909

I am now in the process of building a coroplast velomobile (which is a full body fairing on my tadpole)

Yea! Another coroplast junkie!! :thumb:

http://davidclary.com/images/p38ff.jpg

I painted the inside of the zzipper bubble but left a clear space for the light to shine through.

To your question, I don't think this is a case where 1 + 1 = 2. But two lights is a good idea--more versatility and built in redundancy in case of failure.

I'm a fan of two or more lights, in case one malfunctions.

Then find 2 with current drain equal to one larger lamp. Remember that if you operate them simultaneously they are going to fail within the same time frame. Is it not so hard to carry a spare in the body of the light and use one that is easily opened and changed? I have at least one that does this.

Actually, I think I may have found what I'm looking for.
http://cgi.ebay.com/2x-MR11-LED-CREE-WHITE-or-WARM-160-Lumen-2W-AC-DC-12V_W0QQitemZ190280456800QQihZ009QQcategoryZ20706QQtcZphotoQQcmdZViewItemQQ_trksidZp1742.m153.l1262
I would just have to get a couple fixtures and I should be good to go!
I think.
I will be traveling 20+ mph. Will two 160 lumen lights be good enough?

IMHO you would be better off getting two of the lights AEO recommended, more lumen output without having to do any modifications.

If you have two lights run one on high the other on medium they are not both going to "fail" at the same time. This way you would have one light to get back to your destination. It is also easy to carry an extra set of batteries to swap out.

If you just want to do a DIY project, search the forums, I believe there are better options (more lumen's) in the same price range.

Edit; whoops, just went and looked again at the flashlights AEO recommended, I see they are only a single mode. You could however purchase a two mode and have the option I mentioned above.

Actually, I think I may have found what I'm looking for.
http://cgi.ebay.com/2x-MR11-LED-CREE-WHITE-or-WARM-160-Lumen-2W-AC-DC-12V_W0QQitemZ190280456800QQihZ009QQcategoryZ20706QQtcZphotoQQcmdZViewItemQQ_trksidZp1742.m153.l1262


Interesting that the lamp is R11 and also R16 at the same time ??

"2x MR11 LED CREE WHITE"

"TWO (2) MR16 12V AC or DC Spotlight/Flood Light Bulb"

I will be traveling 20+ mph. Will two 160 lumen lights be good enough?

This all depends on personal preference. I've rode with a Fenix L2D Q5 (180 lumens) and found it completely inadequate. I use 2 dealextreme P7 flashlights, somewhere around 800-1200 lumens combined.

Sometimes I'll run one on medium, sometimes the other, sometimes both on high...if one dies I'm not caught in the dark.

Two 160 lumens might do it. Give it a try.

EDIT (July 11, 2009): I discovered my L2D LED has been damaged for some time now, so my Fenix opinions are not accurate.

Ok, after hours of searching, I found this:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220361086774&ssPageName=ADME:B:BCA:US:1123
Two of those should be plenty. I just hope the 45% beam isn't to wide.
I also found a 3x2watt bulb that would produce 400 lumens, but they would have cost me about $20 more and I am trying to stay under $75. Now all I need to do is figure out how to make turn signals and I'll be set!

Ok, after hours of searching, I found this:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220361086774&ssPageName=ADME:B:BCA:US:1123
Two of those should be plenty. I just hope the 45% beam isn't to wide.

45 is a huge angle. These things are for lighting up rooms not for projecting a beam 30m down the road. Even 15 degrees is marginal for a roadlight. 10 is good.

obviously you should use these with a secondary lens, but it would be better if the original bulb is less wide spread to begin with.

45 is a huge angle. These things are for lighting up rooms not for projecting a beam 30m down the road. Even 15 degrees is marginal for a roadlight. 10 is good.

Really? wow. I was looking for something with a 24-35 degree angle. I can't really find anything very powerful with that narrow of a beam. I found a 3x2watt bulb rated 360 lumens with a 30 degree angle I might pick up. If I were to add some sort of housing with them recessed would that help the angle?

There are lots and lots of choices out there, why not start out with something even vaguely suitable ?

Are you deliberately trying to make life difficult for yourself ?

Why do you want to use house lighting bulbs anyway ?

Output (lumens) will add linearly, intensity will not (lux) because it's almost impossible to make two lights focus act the exact same point. Also, your eyes adjust to the difference to an extent so double the output only really looks like 25%-30% improvement. 2 lights is most beneficial in terms of shaping a beam.

There are lots and lots of choices out there, why not start out with something even vaguely suitable ?

Are you deliberately trying to make life difficult for yourself ?

Why do you want to use house lighting bulbs anyway ?

uhhhh...........
I was going by what most where using in the total geekiness thread
http://www.bikeforums.net/showthread.php?t=42629
There are fog lights that use mr16 bulbs.
What would you suggest? I motorcycle headlight? As long as I can get one that's LED, at a good price, then I'm all for it.

uhhhh...........
I was going by what most where using in the total geekiness thread
http://www.bikeforums.net/showthread.php?t=42629
There are fog lights that use mr16 bulbs.
What would you suggest? I motorcycle headlight? As long as I can get one that's LED, at a good price, then I'm all for it.

Which end of the thread were you looking at ?

It starts 6 years ago so some of the info in it doesn't really apply now.

People were (some still are) using halogen bulbs because of the low price and high output, short runtimes and large batteries being the drawbacks.

What I would recommend would depend on your requirements such as power source, mounting arrangement, required runtime and the amount of light you want.

Obviously the amount you have to spend comes into play, it might be worth considering a multi LED headlight or even HID.

The more info you can provide on mounting and your other requirements the more useful suggestions you'll get on here.

From what you've said so far I would say make your own LED headlights and direct drive them on a nimh or lithium pack to suit light output and runtime.

:thumb:

uhhhh...........
I was going by what most where using in the total geekiness thread
http://www.bikeforums.net/showthread.php?t=42629
There are fog lights that use mr16 bulbs.
What would you suggest? I motorcycle headlight? As long as I can get one that's LED, at a good price, then I'm all for it.

Did you read the whole thread?
These MR16/11 led bulbs in general have poor beam patterns, poor efficiency and probably don't want to spend their lives on a vibrating wet bike.
For a BIKE the best thing, surprisingly, is a bike light. The next best thing is an led torch, there are threads here full of them. Bear in mind you will need to mount them within reach or run an extension to control them.

If its to mount nicely on a fairing you might want to go homebrew/diy. Check out bikeled.org for starters.

Problem with buying a dedicated bike light is that you tend to pay alot for something with great output. There are some great designs out there but the problem is that LED torches are simply a better output/$ ratio especially in the sub $100 arena. I mean my dual P7 setup can hold it's own against anything other than top-tier lights like the secca 700 or other $300 plus lights, but my setup cost half that. It gets even more efficient to build your own LED based lights.

The bike light will have the advantage in terms of mountability and UI for biking but for me its not worth. And the big reason they are more expensive is because of all the R&D that goes into them and because it's difficult to stay on top of LED techology in the market.

Ok, screw the mr16.
This is what I'm thinking now:
A self built single SSC P7 led light
http://www.dealextreme.com/details.dx/sku.12721
I just need to find a driver that I can figure out easily and a 15 degree optical lens.
DX has all the rest. Reflector and heatsinks

I can use my old light for a backup if it dies on me.

The ready made bike lights I can afford are not bright enough for my needs.

Did you read the whole thread?
Did you read the whole thread?

No, just about the first and last 10 pages.
I figured getting a LED mr16 would be the easiest. (still is, actually)
But, if the beams are not the best, I might as well give the homebuilt a shot.
I just hope I don't screw it up.

What I would recommend would depend on your requirements such as power source, mounting arrangement, required runtime and the amount of light you want.

I won't have a power source requirement until I get the light. I am hoping the light will be light enough to mount to the inside of the coroplast behind a clear panel. If not, then it will have to be mounted to either the trike boom or the fairings pvc mount. It must run at least 1.5 hours. I have no idea what the measurements for illumination compare to. All I know is the brighter the better. Someone stated that they tried a 200 lumen light and it was not enough, so that makes me want at least 400 lumens. I have not ridden my faired trike yet, but I may be pushing 30mph on the the flats. Half of my commute is urban, and half rural. The rural half is all nice flat blacktop, so I don't need to look for pot holes. Mainly I just need to be seen. Mostly by the wildlife. I didn't like the raccoon panicking and running in between my tires of my upright last summer. :twitchy:

Ok, screw the mr16.
This is what I'm thinking now:
A self built single SSC P7 led light
http://www.dealextreme.com/details.dx/sku.12721
I just need to find a driver that I can figure out easily and a 15 degree optical lens.
DX has all the rest. Reflector and heatsinks

Firstly, with good heatsinking you can direct drive that LED.

Secondly, save yourself the pain and buy a P7 torch.

:)

If you do go selfbuild you can buy a P7 module, but that is nearly the same price as a P7 torch.

I'd consider making a 3 x R2 headlight instead as heat management is easier to achieve.

:)

I am hoping the light will be light enough to mount to the inside of the coroplast behind a clear panel.
If not, then it will have to be mounted to either the trike boom or the fairings pvc mount.

Buy a couple of P7 torches and mount them on the PVC mount using lockblocks, or be damned with the drag and mount them outside of the fairing. :O

It will double your lighting costs.

I'd consider making a 3 x R2 headlight instead as heat management is easier to achieve.

:)

Ok, got any ideas for a driver and focus lenses? I had found some somewhere, but lost them looking at the P7s

nevermind, I went back to http://bikeled.org/ and got my shopping list.

3, Cree XR-E R2 LEDs on stars http://www.dealextreme.com/details.dx/sku.15943
Driver - http://www.ledsupply.com/03023-d-n-1000.php
2, 5 degree optics - http://www.ledsupply.com/l2-op-005.php
a 5x20 degree optic - http://www.ledsupply.com/l2-op-520.php
3, optic holders - http://www.ledsupply.com/l2-oh-s35.php

So far my total expenses will be approx. $45 USD

I might pick up some heatsinks as well since my light will not have air running over it. I was kinda eyeballing this:
http://www.dealextreme.com/details.dx/sku.15346

Now, anyone have any suggestions for batteries? I am completely lost with those. I get the voltage, but I don't know anything else.

Don't buy a driver until you know what batteries you are using.

You could buy a triple optic instead of all those assorted bits and pieces, it would be much cheaper and simpler.

ALSO - THOSE PARTS ARE FOR LUXEON AND PROBABLY WON'T FIT THE CREE R2's.

The first light I built, I was advised to buy Cree LEDs and Luxeon optics, the Luxeon optics were expensive and didn't fit the LEDs. Have a look at this light: Tri-LED Headlight (http://www.pilom.com/BicycleElectronics/triLEDhead.htm) it's designed for a dynohub but can easily be battery powered.

Batteries (http://www.dealextreme.com/details.dx/sku.5790)

Charger (http://www.dealextreme.com/details.dx/sku.1251)

Triple Collimator (http://www.dealextreme.com/details.dx/sku.1916)

Lastly, you might not need a regulator at all, depending on how you power the headlight.

Here's the ones I've been making Triple LED (http://www.bikeforums.net/showthread.php?t=448060&highlight=) the thread needs updating but it should give you an idea.

Well crap, I already put in the order through LED supply. I'm sure the optics could be modified to fit though, and they are pretty cheap. I have read that it's not a very good idea to run leds with out a driver as well. I think this is especially true since I need to use a battery that will last at least an hour and a half. I have a 24v 20ah that I am using for a power assist and could just tap into it, but I think I would rather have a smaller separate pack for the lights.
Actually, that triple optic looks a bit more complicated to me. All that measuring , drilling, and having to get everything lined up right for the lense. No thanks. Ill stick to the al square light. I'm better with staight lines.

That lens you posted the link to doesn't state an angle either. There is one in your thread from cutter that would work though. Still I'm sticking to the square stuff. Seams like it would be much bigger too

If you went for P7s you could direct drive them off 3.7V batteries, no driver needed. That's what most of the 18650 P7 lights are doing anyway.

Well crap, I already put in the order through LED supply. I'm sure the optics could be modified to fit though, and they are pretty cheap. I have read that it's not a very good idea to run leds with out a driver as well.

There's no problem running LEDs without a driver as long as the supply voltage isn't too high.

Advantages are that it's more efficient and you can get longer runtimes.

Disadvantages are that the light gets dimmer as the battery empties - but at least it doesn't go out suddenly with out any warning.

You might be able to get the optics to work with the LEDs, but having tried this myself I can tell you that placing the emitter at the correct focal point is very difficult and a small amount - less than 0.1 mm can make a lot of difference to the beam, that is if you manage to get a beam at all.

If you don't want to try using a triple colimator there is another alternative you could pursue.

Here are some Edison (http://www.dealextreme.com/details.dx/sku.4282) LEDs that are nearly as good as Cree R2s but fit luxeon optics.

http://www1.dealextreme.com/productimages/sku_4282_1_small.jpg

Although they are pictured without bases I've bought these twice and both times they came with bases (bases are very cheap, anyway).

You could use 3 of these with your optics and save the R2s for another project.

After discovering how difficult it is to get a cree in the right place using luxeon optics I used these.

Hope this helps. :thumb:

Alternatively buy some separate optics that fit straight onto the Crees 23.36mm Optics (http://www.dealextreme.com/details.dx/sku.1920) these clip onto the Cree LED and work very well.

Or you could do both, buy some of the optics to go with your Crees AND buy some of the Edison LEDs to use with your Luxeon optics - you'd have two lights and the comparison might be interesting.

:)

ps. I'd change the LEDs or change the optics

Well crap, I already put in the order through LED supply.
They have a few sorts of cree optics (http://www.ledsupply.com/led-optics.php), call them and see if you can change the order.

Thanks for the heads up on the Edisons, Unknown. I haven't order the crees yet and this being my first time, those will work since they are a bit cheaper. (and I have a limited budget)

Got the 3 edisons and a pack of cheap heatsinks - $17.08

Some Arctic Alumina Thermal Adhesive - $9.99
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=120372972077


I'm at a total of approx $72

Spending a bit more then I wanted to, but I'm sure it will be worth it.

As far as batteries go, I think something like this is best:
http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=2486
If I can get 4 hours of run time that would make my complete round trip if needed. Must of the time only one way is dark.

As far as batteries go, I think something like this is best:
http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=2486
If I can get 4 hours of run time that would make my complete round trip if needed. Must of the time only one way is dark.
[/color][/size][/font]

Z.14.8V 4000mAh Li-Ion Battery - # Overdischarge ( < 11.0 V)

Wired BuckPuck 3023-D-N-1000 - the input voltage must always be higher than the total forward voltage drop of the LED junctions connected in series (2.0V for DC models).

If you intend to drive the LEDs at 1000mA it would make more sense to direct drive them, especially if you are looking for longer runtimes.

Ref. post #33 "Don't buy a driver until you know what batteries you are using"

Hi,

I've been looking at reptilian's planned light specifically the battery and buckpuck.

Can someone in the know have a look at my conclusions and see if there are any glaring errors ?


-----------------

1) the 14.8V battery is protected and will cut out at 11V

2) the buck puck requires a higher voltage in than out (+2V for DC models) from the spec sheet

3) at 1A each LED HAS to be at 3.7V - 3.7 x 3 = 11.1V has to be supplied by the buckpuck

Once you start powering the LEDs the battery voltage will slowly drop, when it gets to about 13.1V the buckpuck will no longer power the LEDs.

The battery will probably be less than 50% discharged.

Although the buckpuck output voltage and current will be constant (11.1V x 1000mA) the input voltage and current won't be - the buckpuck will increasingly demand more current as the voltage drops.

The LEDs will run at full brightness until the battery voltage drops to 13.1V.

If you ran two LEDs from that buckpuck they would require 7.4V, therefore the input voltage would be 7.4 + 2 = 9.4V, comfortably below the 11V battery cut off.

You will need to find a different buckpuck, different battery or a boostpuck and different battery.

Or go direct drive.

You are connecting batteries in series to increase the voltage, just to then use complex electronics to drop the voltage back down again.

I haven't used this buckpuck, does anyone know exactly what it does if the input voltage drops below what is required ?

Any thoughts anyone ?

Is there any way I can edit the title of this thread. It's went pretty far off the original subject, and I don't think it's getting as much attention as it could with something like, "My first LED light build"

Is there any way I can edit the title of this thread. It's went pretty far off the original subject, and I don't think it's getting as much attention as it could with something like, "My first LED light build"

Just start a new thread and put the info you want in the first post.

New thread started:
http://www.bikeforums.net/newthread.php?do=postthread&f=259

Really? wow. I was looking for something with a 24-35 degree angle. I can't really find anything very powerful with that narrow of a beam. I found a 3x2watt bulb rated 360 lumens with a 30 degree angle I might pick up. If I were to add some sort of housing with them recessed would that help the angle?

A 25 degree flood is still a wide angle for bicycle use. I run 12 degrees and have had some 7 degree spots (didn't fit in the lamp right:mad:). I use a 25 degree flood for my tertiary light. Two 12 degree are my primary (helmet) and secondary (handlebar) lights. If I had to, I could lose the flood and not really miss it.

A 25 degree flood is still a wide angle for bicycle use. I run 12 degrees and have had some 7 degree spots (didn't fit in the lamp right:mad:). I use a 25 degree flood for my tertiary light. Two 12 degree are my primary (helmet) and secondary (handlebar) lights. If I had to, I could lose the flood and not really miss it.

Yeah, I think we've already covered that. thanks though:thumb:

New thread started:
http://www.bikeforums.net/newthread.php?do=postthread&f=259

Looks like my thread didn't take for some reason :(

here we go:
http://www.bikeforums.net/showthread.php?t=512929