LED Swap
#23
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Well I'm only 25% done and it is not taking much time, its just I don't have the time to do it. The door switches took about 2 hours and the the fog/trip and gas/boot switches took about 45 mins. The rest will be more involved. I have the gear selector, instrument cluster, radio, climate control, steering wheel controls and the garage opener switches still unchanged,so I still have a long way to go.
I am also very scared of breaking one of the wood pieces so that is why I am taking my time.
I am also very scared of breaking one of the wood pieces so that is why I am taking my time.
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superjag, if the leds are blowing out on you, then you are pushing too much current through them. You should only be running about 15 milliamps through the LEDs. If you need some help calculating the proper resistor to use with an LED, let me know. I have done a lot of work with LEDs (made me a set of tail lights for my truck with 390 LEDs per side). As long as you keep the current down around 15 milliamps, the LEDs should outlast the car.
#37
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Thats Awesome!!!!! Super Jag. [sm=smiley20.gif]Thats exactly what I want to do. What size are the bulbs? How many did you need? What resistor? Where?
Therrmmo....can you do those calculations and break them down into something a simple minded girl like me can understand.[sm=lol.gif]
Therrmmo....can you do those calculations and break them down into something a simple minded girl like me can understand.[sm=lol.gif]
#38
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queenB, when working with LEDs, there's 2 pieces of information that you need to know (not quite as simple as standard lights). The two bits of information you need to know is the LED voltage and the LED max current. All LEDs have some piece of paper that comes with them stating these values. So, it isn't a hard thing to find. Not to mention that most LEDs are built to the same specs (ie, 3.6 VDC and 30 milliamp max). There's a few out there that allow up to 100 milliamps (normally the 10mm, super brightLEDs) and others that only operate on 1.8 VDC. So, before using the below calculations, just double check the specs.
Keep in mind that the current flowing through the LED has very little effect on its brightness. As long as you keep the current away from the lower end of the current scale, it will be fine. So, using a standard LED with a max current of 30 milliamps, as long as you maintain the current above 5 milliamps, the brightness will be the same. I bring this up as this makes dimming an LED more complicated than a standard bulb. Dimming a LED can be accomplished2 ways. LEDs are rated in MCD (millicandela, think of it the same as lumen or candlepower). The big difference between MCD and other light ratings for standard bulbs is the MCD rating is a directional rating (ie, very bright head on, but off to the side you get very little light output). So, by going with a lower MCD rating, the LED will not be as bright. The other way is pulse the LED on and off at a high rate of speed. The brightness is then controlled by how much on time there is in relation to off time. Most new cars have gone to this type of dimmer. So, no worries there. I would need to double check to see if our Jags have that style dimmer.
As for the calculation, look at the below equation:
resistor= (14.4 VDC - 3.6 VDC) / 0.015 amps . Keep in mind that most cars operate at 14.4 VDC, so, this is a constant. The 3.6 VDC is the normal operating voltage of an LED. If you are using something different, adjust this voltage to match the LED. Finally, 0.015 amps is the same as 15 milliamps (1 amp = 1000 milliamps). So, using the data in the previous equation, that would work out to 720 ohms. Since there is no 720 ohm resistor, step up to the next larger one (less current is better for LEDs than more). So, you would need to use a 750 ohm resistor. If you don't feel like doing the calculations, you can get online and go to http://ledcalculator.net/and it will do all the calculations and select the best resistor for you. All you have to do is answer the questions.
hopefully I am not going above your head. If I am, just hollar. I will break it down even further or explain a specific topic using different words. My job has me trying to teach mechanics how to mess around with electrical stuff. So, you can imagine the joys that I have. I have found that they do understand what sparks and arcs are. LMAO.
Keep in mind that the current flowing through the LED has very little effect on its brightness. As long as you keep the current away from the lower end of the current scale, it will be fine. So, using a standard LED with a max current of 30 milliamps, as long as you maintain the current above 5 milliamps, the brightness will be the same. I bring this up as this makes dimming an LED more complicated than a standard bulb. Dimming a LED can be accomplished2 ways. LEDs are rated in MCD (millicandela, think of it the same as lumen or candlepower). The big difference between MCD and other light ratings for standard bulbs is the MCD rating is a directional rating (ie, very bright head on, but off to the side you get very little light output). So, by going with a lower MCD rating, the LED will not be as bright. The other way is pulse the LED on and off at a high rate of speed. The brightness is then controlled by how much on time there is in relation to off time. Most new cars have gone to this type of dimmer. So, no worries there. I would need to double check to see if our Jags have that style dimmer.
As for the calculation, look at the below equation:
resistor= (14.4 VDC - 3.6 VDC) / 0.015 amps . Keep in mind that most cars operate at 14.4 VDC, so, this is a constant. The 3.6 VDC is the normal operating voltage of an LED. If you are using something different, adjust this voltage to match the LED. Finally, 0.015 amps is the same as 15 milliamps (1 amp = 1000 milliamps). So, using the data in the previous equation, that would work out to 720 ohms. Since there is no 720 ohm resistor, step up to the next larger one (less current is better for LEDs than more). So, you would need to use a 750 ohm resistor. If you don't feel like doing the calculations, you can get online and go to http://ledcalculator.net/and it will do all the calculations and select the best resistor for you. All you have to do is answer the questions.
hopefully I am not going above your head. If I am, just hollar. I will break it down even further or explain a specific topic using different words. My job has me trying to teach mechanics how to mess around with electrical stuff. So, you can imagine the joys that I have. I have found that they do understand what sparks and arcs are. LMAO.
#39
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Queen, one last answer to a question that I get asked a lot: it doesn't matter if you go from the power supply through the resistor, then through the LED to ground or go from power supply, through the LED, through the resistor, to ground. Electrically it is the same thing. The big thing is to keep all this in series. Then as you add more LEDs, all these will be put in parallel with each other.
Another thing to keep things simple is to run a single LED with a single resistor. When you start mixing multiple LEDs with a single resistor or other combinations, things get much more difficult to deal with. Follow the KISS principle.
Another thing to keep things simple is to run a single LED with a single resistor. When you start mixing multiple LEDs with a single resistor or other combinations, things get much more difficult to deal with. Follow the KISS principle.
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