Making emergency lighting

[JFD140]

Ok so i am currently in small business making GEN I emergency vehicle lighting from scratch but i think i am ready to make the move to GEN III TIR style lighting.

Basically my problem is i dont know where to begin with the R&D aspect.

Can i even make such lights in my own home? I would be laying out probably $1000 to complete the first working light. I intend to have custom extruded housings with lexan lenses.

Anyway, where is the best place to get started?

I want to use 1 watt LEDs, with a TIR style focused 40 and 25 degree lenses.

My biggest learning concerns is that these lights to my understanding require a constant power driver in them? I do not know how true this is but that is why i came here. To learn from the best.


So all help on where to begin experimenting with individual lights or circuit boards to begin with would be excellent.

THANKS!

-Zach

 

[StarHalo]

Re: Making GENIII emergency lighting

I had to look up "Gen III emergency vehicle lighting", it looks like they just mean using modern power LEDs for emergency strobes. That we can do, and probably for a whole lot less than a grand.

Here's just one retailer that has a whole barrage of lenses and LEDs: http://www.led-tech.de/en/index.html

 

[JFD140]

Re: Making GENIII emergency lighting

finding parts are not so much my current issue.


I need help understanding the workings behind these LEDs.


I do not know how to heatsink them, what kind of resistor setup they need.

I have been told instead of resistors they need a constant current driver or something built in,

 

[StarHalo]

Re: Making GENIII emergency lighting

Modern LEDs work the same way as any other LED power-wise, just line up the Vf and mA values and it'll light. In an application where you're always going to have a consistent 12 volts, I'm not sure why you'd need a regulator (but I'm not a circuitry scholar, so someone else may have some good reasons). Here's a very good LED circuit resistance caluclator that will even draw out the schematic for you based on your LEDs/numbers: http://ledcalc.com/

In a vehicle application, heatsinking isn't usually a problem since there's metal and airflow everywhere - as long as the LEDs are thermally mounted to the housing and the housing isn't too small, it should be fine.

 

[tebore]

Re: Making GENIII emergency lighting

Modern LEDs work the same way as any other LED power-wise, just line up the Vf and mA values and it'll light. In an application where you're always going to have a consistent 12 volts, I'm not sure why you'd need a regulator (but I'm not a circuitry scholar, so someone else may have some good reasons). Here's a very good LED circuit resistance caluclator that will even draw out the schematic for you based on your LEDs/numbers: http://ledcalc.com/

In a vehicle application, heatsinking isn't usually a problem since there's metal and airflow everywhere - as long as the LEDs are thermally mounted to the housing and the housing isn't too small, it should be fine.

Because on a car you're not dealing with a constant 12V energy source. You're getting from 10v - 32v spikes.

WRONG on that last count. With LEDs especially in commercial applications heatsinking is very important. I don't know if you've seen some of the "GenIII" products out but some emergency vehicles were parked and I got a closer look and those light bars are just billets of aluminum with LEDs, optics and I assume electronics hidden. When designing for commercial apps gut feelings aren't good enough you need to do the power dissipation calculation and how much mass is needed and thermal resistance is in the system. Especially when you get sued when your product fails on a bunch of Police crusiers.

So remember the following are important:
1. Power regulation
2. Heatsinking
3. The LEDs used. You don't want dinky no-name 5MM or Counterfeit high power LEDs. Luxeon and Cree are the names to usually pop up here
4. Good weather sealing, I'm sure you have plenty of experience.

 

[JFD140]

Re: Making GENIII emergency lighting

so where should i begin to learn about how to actually go about making a prototype...

also emergency vehicle lighting is meant to run off of 12 to 14v constant. If you hit spikes of 32 then you wired it to the wrong part of the car and its your own fault.

If i put 3, 1w LEDs in a line with 12v behind them then the calculator says i dont really need resistors, but my heat dissipation will be an issue.

Sorry for dumb questions but id rather ask and learn then spend money figuring it out the hard way.

 

[Mike Painter]

Re: Making GENIII emergency lighting

so where should i begin to learn about how to actually go about making a prototype...

also emergency vehicle lighting is meant to run off of 12 to 14v constant. If you hit spikes of 32 then you wired it to the wrong part of the car and its your own fault.

If i put 3, 1w LEDs in a line with 12v behind them then the calculator says i dont really need resistors, but my heat dissipation will be an issue.

Sorry for dumb questions but id rather ask and learn then spend money figuring it out the hard way.

I'm not sure who your target market is but unless is NOT the fire service or you only plan to sell these on new vehicles, your comment about it being our fault will not fly.
It's common to have old vehicles and it's common to find poor wiring and it's common to have problems with these wires and it's commonto have sags and surges that can't be accounted for, and it's common to hook up something new to the closest 12 volt source and hope for the best.
Some of out vehicles are over 10 years old and one is over 30.
We are a small 99% volunteer department, one of only two in this county with paid staff.
Most are poor and can't afford 300k for a new machine.

It's also common for a surge in ANY part of a system to pass through all of the system.

Police cars are a bit cheaper and they can afford and have to swap out more often.

But in any case all you have to do is tell one department it's their fault and you will have made your last sale.

If you were the only vendor in Californai everybody would move back to the legal requirement for an emergency vehicle; one steady burning red light visible to the front.

 

[JFD140]

Re: Making GENIII emergency lighting

Mike i think you got the wrong idea from my statement.

I am ultimately asking how do i make a heatsink and a constant current driver for the lights that will all fit into a 1 to 1.5 inch housing.


I am actually thinking about finding a company that will assemble all the circuit boards for me, and all i have to do is put them together in a housing.

Does anyone know of a company that offers the services of both acquiring the parts i need, most likely luxeon K2s or rebels with TIR style reflectors. And then assembling them in circuit boards with 3 to 6 LEDs and reflectors each?

Would be prepared to order $1500 worth at once.

 

[JFD140]

Re: Making GENIII emergency lighting

this is what i have found to describe what i want to make circuit board wise.

I need drivers such as this

http://www.luxeonstar.com/buckpuck-1000ma-dc-led-driver-pcb-mount-p-9.php


and the ultimate finished product would be similar to this
http://www.luxeonstar.com/luxstrip-light-engine-luxeon-k2-leds-600-lumens-15deg-optics-p-60.php

But with more LEDs per inch. And less expensive to mass produce.

I do not necessarily need to go with luxeon star especially not for the prototype.