?!?!Multi-Emitter Spotlight!?!?

[Aepoc]

I recently acquired a LSI Nite Tracker S/R 500,000cp spotlight. It has an incandescent bulb, but I am thinking of converting it to a multi-emitter seoul.

Does anyone make multi-emitter heat sinks for anything bigger then a mag or am I going to have to custom fabricate something?

The light has two lead-acid batteries wired in parallel. The batteries are 6 volts and 5 Ah each. I have never messed with lead-acid batteries before and I was wondering if there were any reasons why they shouldn't be wired in series to increase the voltage.

Does anyone know of any reasonably priced on/off (single mode) circuits, or should I go for a resister?

Any thoughts, comments, or other input would be appreciated.

 

[Illum]

I suppose you can fit a server grade heatsink in but it would most likely be very heavy...

plus the assembly of little reflectors would put out alot less throw than the halogen

but It sounds good

 

[Aepoc]

I have an old graphic card heat sink that I was thinking of using. I'm only worried about focus.

I only need it to throw about 15 feet... It will be used for machine repair and maintenance. I am thinking that the flood from the small reflectors would be more useful than the single large smooth reflector.

 

[vector_joe]

Sorry, don't have much to add, but it sounds like a cool project. Please post pictures and updates.

 

[HaPPI]

Old CPU heatsink might be large enough. Changing the battery wiring means you need a different charger. OR you could get a gaggle of Crees with reflectors, as in

http://www.dealextreme.com/details.dx/sku.3214

but then you are talking a chunk of $. But it would rock! If the batts produce 6v these modules would work for you.

I've got one on order to play with. Hope it comes soon!

 

[Illum]

well, focus wouldn't be a concern if you mount something like fraen lenses on holders directly to the heatsink
http://www.luxeonstar.com/sub_category.php?id=122&link_str=121::122

A resistor is on the cheap side but a DC-DC boost circuit is possible and that may allow you to resize your battery pack. :naughty: as the original cell is most likely a Sealed Lead Acid intended for high current draw from the existing halogen lamp, you could swap that out and use say...18650s instead

look up Bucktoot or Powerpuck from luxeonstar.com and see if they seem ideal. although they are originally made for driving luxeons at 350ma, I suppose they can be used with others:candle:


also, CPU grade heatsinks are intended for forced air cooling [hence the extruded fins] but since you will be using it in a enclosed environment you might want to consider other options as you'll be mounting it on plastic and theres always that the concern of melting something on prolonged runtimes

by the way, how many LEDs do you plan on using?

 

[Aepoc]

I am planning on using 4-6 emitters.

Good thought on the plastic-metal connection... I didn't think of that one.

I would like to reuse the batteries because a new charger and new batts would be too expensive. If this light turns out alright, I would be upgrading all in use at the local Georgia Pacific mill, and 100 bucks for one light isn't much... a hundred bucks times 20 lights can get expensive.

 

[Illum]

do you have the specs for the existing battery?

 

[Aepoc]

Yes. I have done some research and have found a data sheet for the batteries. The light is composed of two of these batteries wired in parallel.

http://www.sunnyway-battery.com/Pro_Img/200512301057440213.pdf

They are lead acid, 6 volts, and 5 amp-hours capacity each.

 

[Illum]

there are regulator units that accept 5-32VDC as input to drive multiple LEDs, such as the buckpuck that you can choose between 350, 700, and 1000ma drivers but if your looking for a cheaper alternative I guess you could rely on high wattage resistors.

add the voltages when you connect the LEDs in series and add current when parallel...say if the LED requirements are 3.5V @ 250ma three in series would be 10.5V @ 250ma. and 4 banks of 3 in series would yield a requirement of 10.5V @ 1000ma. if can the batteries be wired in series then you could use 12 LEDs by a simple resistor and lots of thermal epoxy, especially for the resistor

if you prefer to leave them in the existing 6V configuration...then compute with the method above for an ideal amount of LEDs to use. I would prefer to stay below one amp of current consumption because
1- the power requirements and heat dissipation of resistors [if your planning to go that route] may be a concern
2-you can get away with using thin 22-gauge hookup wire without any risk of something catching fire

 

[sysadmn]

If you decide to go with optics instead of reflectors, look around. Some of the companies offer an "mr-16" optic that covers 3 emitters. It's designed for halogen track lighting replacement, but they have a variety of models.

One vendor is http://led-spot.com/index.shtml
Triples and Quads: http://www.led-spot.com/p_triple.shtml
Their minimum is 3 pcs of a single type, but ship the next day. Haven't bought anything yet - that project is on my todo list.

 

[Illum]

so thats where electrolumens got those nice looking optics for the tristar phasers

 

[Aepoc]

Thanks guys for the useful info. I am assuming the optics are spotty. The average distance of use is about 20 ft. I think I should go for a more floody configuration.

 

[Illum]

Thanks guys for the useful info. I am assuming the optics are spotty. The average distance of use is about 20 ft. I think I should go for a more floody configuration.

Fraen Focusing Lenses alone allows everything from wide 40 degree beams to 6 degree narrow beams and features elliptical projection lenses for applications such as headlights...other options are available

since most manufacturers use something like a diffuser for flood, optics became emphasized for spot, but theres flood options as well, you could install optics on a few leds but not all, and the rest would simply dissipate around....:candle: