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another classic basketcase enquiry, you have all been waiting for,
now,
have small led battery light, that originally came with 3 1,5volt batteries,
brainwave bear decided to rewire it, and connect it to 12 volt car circuit, for internal lighting.
works a treat except for one thing,, is giving off too much heat, this is not right for led,s??
so wondering whether all i have to do is put a 4.5volt capacitor in circuit?? or diode? or whatever electronic gurus call them?
also if i put another ligtht in circuit, do i need to increase diode/capacitor/ to 9volts?
or have it at 4.5volts?
auto elec said they are multivolt led,s
any electronic gurus in fastlane? know answer to this
thanks already
bcb
said the weathercock to the wind,> "how tedious and monotonous you are, can you not blow in any other direction, but in my face!"
and the wind did not answer, it just laughed in space.
k.g/ |
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If its getting too hot, the LED wont last long.
You will need to put a resistor in series with the LED to reduce the current.
There is a formula for working it out, but you need to know what voltage (V) and the current (mA) rating of the LED is. Obvi |
Cheers,
Mick
_______________________________________________________________
Judge a successful man not on how he treats his peers, but on how he treats those less fortunate. |
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thats it commnut,,,,resistor,, thats the doobylacky whatchacallit i was looking for!
there is about 10led,s in each light,, so if i put a 4.5vresistor in the power supply wire,
will this do it?
cause the 3 batteries were supplying 4.5v?
tried learning |
more than basketcase than a bear!
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That makes things a bit more complicated as you cant tell how each individual LED is connected.
Need more info. What colour is it?
LEDs arent like normal light globes, they dont have a set resistance if you put a voltage across them. They are designed
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if i wanted to run a 6 volt appliance in a 12 volt situation i could just stick in a 6 volt resisitor ahead of it and that would sort it out.
I cant do that with led? say, there are 3 at 1.5 volt, =4.5 volts, stick in a 7 volt resistor?
my father used
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to run a 6v appliance of 12volts ul want to have a resistor in series with the same resistance as the 6v appliance u r trying to run this would split the voltage 50/50 giving you the 6v. but it will apprx double your current draw
with the globes they wou
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tell ya.
all too gawd damned complicated for me.
i thought of getting bigger 4.5volt battery, and running them of this, then recharging biggerer battery,
but i think this leads to even more problemos?
ok> details>>
20 led globes in light, su |
more than basketcase than a bear!
DOH!!! |
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well yall,
i dundadit,, put 2 56ohmn x .5 watt resistor,s on light, they were quite warm, but led,s were alot cooler.
so probably need closer settings?
will experiment
cheers
bcb
said the weathercock to the wind,> "how tedious and monotonous y |
more than basketcase than a bear!
DOH!!! |
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I forgot about that bit. 56 ohms at that current will be dissipating over 2 watts, seeing as they are only 0.5W resistors they might get a little hot. If you could find a 5W wirewound resistor of about that value that would be better.
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bcb, why not use a Potentiometer Linear 5 watt, this is a variable resistor that would allow you to virtually use the Potentiometer as a Dimmer control for the LEDs. If you use a Dual gang Potentiometer you could split the circuit into two and control bot
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phew!!! oz!! i cant even spell potenntioometere!! getting mighty fandangled here!!!
but hey sounds great,,
i will suss out one of them,, next time i am in a electronic shop..
thanks for that,,
by the by,,you dont know where i can get those high po |
more than basketcase than a bear!
DOH!!! |
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http://www.jaycar.com.au/Try those guys. Probably have a store near you. They have a whole heap of LED auto replacement lights. I got an interior LED light from them. Brighter and sucks much less juice so you wont run you battery down if you leave your
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thanks blue light and all,
i will try to find wire wound 5v resistor,, and or potentiometer,,
must ask next time i am in jaycar bout dash led,s
have asked lieth for rare spares to carry them, as i am sure all our classics could use them?
cheers
bcb
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more than basketcase than a bear!
DOH!!! |
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