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Class : Apprenti
Posts : 2
Registered on : 25/02/2008
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Hi
Just got 3 Led IR, dont know the MA, only know they are 3V, i used the Led calculator wizard, and tried the assembly with 100ma and 70ma to a 9V volt Batery.
With both assemblys the resitors are getting hot, i m afraid to burn them, or its normal some heat?
Thank you
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Class : Apprenti
Posts : 24
Registered on : 05/02/2008
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you got high load on the resistor or resistors if you put 3(paralel cuircut).
use 5V battery but you have to put other resistor value to
gain same current. you'll get lower V on R that mean less power dissipation
you are wrong for shure about LED V , V goes arround 1.1-1.7 V depending of curent. If you put something like that in calc you cant go wrong)
Edited by vranac on 06/03/2008 at 01h51. |
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Class : Apprenti
Posts : 49
Registered on : 13/02/2008
Off line Www
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Some heat is normal, but it sounds/reads like you are getting WARM resistors.
-Are you sure the Diodes are 3 Volts, sounds wrong to me (usually the tend to be 1,5 V). -are your diodes geting warm too, because then they are over powered.
A resitor is converting/using/eating energy and produces heat as a result.
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