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Puddle Jumper
Posts: 12
| Ok, here's a question for all you engineers out there. I'm trying to install LED pods to the tourpak marker lights, everything fits fine. My problem is the LED's are only 4.5 volts, my question is how can I reduce the voltage to the pods without burning them out? Any help would be great. Thanks
Forzy |
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Cruiser
Posts: 64
Hot Springs Village, Arkansas | Look on the post for an auto TomTom gps mounted on a Vision. He described a method to transform voltage(required) from fairly available parts source. Hope this helps. Alan |
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Puddle Jumper
Posts: 12
| Thanks Alan, I'll check it out.
Forzy |
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Cruiser
Posts: 208
Wichita, Kansas | LED's aren't a significant power draw and the current does not fluctuate so a power regulator is way overkill. Normal current is only about 20 milliAmps each, so a resistor in line with the LED's will normally be enough and will not run hot. All the pods I've run across have the resistor built in and are already set up for 12 V. Is this something you made yourself? Anyway, presuming this thing has no resistor, normal Vics run about 14 V when running so you will need to drop about 9.5 Volts. At 20 mA, that's R=E/I=9.5/.020= 475 Ohms. 470 is a standard value that will work well. The power would be P=E*I=9.5*.02=.19 Watts. Since this will be in the trunk it probably won't have good heat dissipation so go with at least a half watt unit. This all presumes there is only one LED in the pod. We could repeat this calculation for however many are in there, but the easiest way is just hook up a resistor for each LED in parallel (side by side, not in line). Should work great and cost about a buck. PM me if you have any questions and I'll be glad to help you figure it out. |
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Cruiser
Posts: 137
Houston, Texas | Found this on the Custom Dynamics site (LED vendor)......its a LED resistor calculator, hope it helps.
http://www.hebeiltd.com.cn/?p=zz.led.resistor.calculator
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Cruiser
Posts: 297
VA | Forzy, I was the one that hooked up the TomTom. If you just want to cut voltage, go to radio shack and you can buy a voltage regulator, it's probably around $2 or so. Might want to but the heat sink that screws onto the back of it, maybe a dollar more. But that takes any voltage up to 24V down to 5. THey may alo sell one for 4.5V. Small investment. The amps on the LED's are going to be pretty small like Kansas said.
Here is a link for an adjustable voltage regulator from radio shack: http://www.radioshack.com/product/index.jsp?productId=2062601&y=7&x...
It's $2.29. If this is going in the trunk, then should be no problem. It is very small. This is basically the same thing that is inside your cigarette light chargers just without the case. Hope that helps.
Edited by divesharc 2009-06-28 8:38 AM
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LED pods for tourpak
