Newbie trying to spec my first Hotwire Incan...getting confused!

[SamurI]

Been a lurker for some time and now taking the plunge on my first build.:huh:

I'm basically trying to put together a set-up based around the bulb for a specific purpose.

The bulb i intend to use is an MR16 12V 50W bulb.

Now i would need a maglite C or D host (correct?) due to the bulb fitting straight into the head.

Based on my quick calcs the bulb will draw about 4.16 amps (or according to some of the test data, probably slightly more).

I intend to use one of the GU 5.3 bulb holder kits available so no problem on that but my main stumbling block is on the battery choice.

What sort of battery set-up am i looking at that will give me, if possiable, a 1hr or more, intermittent runtime?

I would like to keep close to a 12V output due to the bulb use, bt a regulated output is not nessecery.

Thanks in advanced guys.

Edit* Just doing basic maths means i wont be getting anywhere near the hour runtime, so as long as i can really.

Ben

 

[Conte]

The only battery I think think of that would come close is an 26650 IMR.

http://www.batteryspace.com/limnnirechargeable26650cell37v4000mah10arated148wh.aspx


3-cells = 10.8 - 12.6v @ 4000mAh with would give you right close to an hour runtime with that bulb. Actually, as the voltage declines to the lower level so would the current draw.

You are technically underdriving the bulb, so you won't get peak output all the time, but a typcial Li-ion battery does sit at around 4v for a good chunck of it's capacity life. Batteries are also known to sag under load, but an IMR cell holds it voltage pretty good under heavy load.
If you add a softstart you might be able to go as high as 4 cells for some extra added boost.

You can fit 3 of these cells in a 2D with a Fivemega 65mm adapter, and turning the spring around around. Or you can fit these 3 cells in a 3D with a slight mod to the tail cap.

I have a tail cap mod tutorial illustrating these methods HERE.

Two other options are, a 4C mag is the perfect length for 3 of these cells, but is just a tad narrow. If you are lucky you can Jam them in as a tight fit, or maybe get someone to bore it out for you.

If you are Nicely bankrolled, Fivemega makes some exotic 4x26500 bodies that will fit 3 of these cells found HERE.

If it were me, I'd rig it in a D mag and pick up one of AW's Incan Drivers.
That way you can dim the bulb and greatly extend the runtime when you don't need full output.

If you are going for runtime, I'd maybe consider a lesser output bulb.
Even a 10 watt deal can seem wicked bright when you are in the pitch dark.

What's your application ?

 

[Echo63]

I ran a similar setup in a bored 3d mag, running a 20w and 12x AA rechargeables (2 extra to cope with the voltage sag)
it worked, but it wasnt overly impressive, it did produce a nice big wall of light , but my Pila GL3 at the time produced a similar amount of light.
The IMR cells look like an interesting idea, and some 12v downlights can handle a large amount of overdrive too, like 16-18v, so 3 or 4x IMR 26500 will give you the power you seek.

be careful soldering the adapter to the switch too, it is possible to melt the switch assembly and have it not work properly (i did it to mine)

 

[Conte]

Seems those IMR cells I recommended are out of stock.

I do recall happening apon a Li-Ion D cell, that I think was about 5000mAh. If I can remember, I'll post it here.

Edit: Xtar Lights.

 

[lctorana]

I have a 4D Mag with a 12-cell holder and the GU5.3 socket, and the results are superb.

The "Radium Halogen MEGA IRC" lamp is the best I have found, more than doubling the lux of a standard or dichroic MR16, but I'm still looking for the narrow beam version.

 

[SamurI]

Firstly i want to thank those that reply for such interesting and useful informtaion!!!

Its your fault im now still up at 4am looking at websites for batteries, drivers and tube extensions!!:thumbsup:

@Conte - Thank you for going to the trouble of listing all my options out and giving links. It makes it so much easier to find such rather than spending hours trawling through the search results.

The application is for car detailing and using it to spot paint defects. I have found a bulb in MR16 format that is perfect, hence why a need to build a hotwire mag around this. There is a 30w bulb of the same spec which would give me better work time but obviously at the cost of lumens! Im getting both bulbs to try though.

Looking at all your information i think im going to go with 4x 26650 cells (which are back in stock now) in a 3D with 65mm fivemega adaptor. Then i'll run it through Jimmy's regulated incan driver and KIU socket.

This'll mean i can try it on both 3 or 4 cells to see if i really need the extra voltage and can hopefully get a bit more run time by using the regulated and switchable driver.

On this i notice the 26650 cells are not protected. Is this correct, and if so should i looked to purchase a PCM with them or will the protection offered by the driver be sufficent?

Also (sorry for all these questions) what sort of charger should i be looking for with these IMR cells?

@Echo65 - The spec sheet i have on the bulb in mind do give data for overdrives upto 16V.

@lctorana - Im interested in the radium lamp, i'll have to look one up and try that.

Thanks again

Ben

 

[Conte]

Oh well, if this is for work purposes, and you want as close to 12v as possible, I would maybe suggest using Lifepo4 cells.

Problem is, they don't come in as high of a capacity. Probably about half hour. But then you could probably get a second set for the same price.

4-cells should run that bulb right in the sweet spot giving you 12.8v.
You wouldn't need a regulator and could go with the cheaper incan driver.

The other con is, charging them is a *****. An economy charger does 2 cells at a time, and is soooo slow. But if you got yourself a good hobby charger, with a balance charging cradle, which, I would recommend with the IMR also, you could whack them proper and have them back up and running in no time.

If you were not planning on running the light for more then a half hour at a time, you could even drop the batteries on the charger between use.

I'm going to be posting a description of this charging system I've described soon. By next week it should be up.

Going back to the IMRs. You won't get more runtime out of a regulated system. Now with Lions running an Incan. When the Lions run down, and they hit their cutoff point, they are done, and you should not push them any further. And if you set up the regulator wrong, so that it show full output while the batterys are running into cutoff, you're asking for trouble.

What the regulator WILL do on the other hand, is, if you feed it more voltage then the bulb needs, it'll maintain, a more consistent brightness for the duration the capacity.

Here's the thing with the regulator, you have to get buddie to program it first. So unless you get the FULL kit that allows you to program it youself, its a set and forget situation, so you have to decide ahead of time what you want to do with it. IE, you have to be certain how many cells you are going to use.

You dont' need a protection circuit, because, if I remember correctly, that is a feature of the regulator, tell the guy you are using 4 cells, and he can program it to turn off automatically, or warn you, when your batteries are done. Hence why you have to make up your mind ahead of time.

If you are going with the regulator, I say, go 4 Cell. You'll get perfect 12v fed to the bulb right down to the point the batteries are ready to cut off.

Meanwhile, IMR's are regarded as a "safe" chemistry. They are a Lithium Ion Manganese, (if I spelled that right) technology. Designed for lower capacity and higher current output. Normal Lion cells that are just called Li-ion, are a Lithium Ion Cobalt technology. They are high capacity, and low output, usually about 2c. They have the same energy density as TNT. The Colbalts are the ones that are known to be dangerous, and need to be protected.

PS: Sorry for all the answers, I talk alot when you get me going, lol.

 

[bouncer]

If that bulb has a 2000 hour life you can overdrive it a bit and get a much more impressive output. I believe someone got a couple thousand lumen build.

found Fivemega's sale link the 12v bulbs can be pushed to 18.5v


http://www.candlepowerforums.com/vb/showthread.php?t=160915