What is a "Passive" LED

medicop88

Member
Apr 11, 2011
221
Rhome, Texas
I keep seeing posts for passive  LED products. I understand that a smart LED has a flasher built in, but what does passive mean? Are they more or less effective?
 

medicop88

Member
Apr 11, 2011
221
Rhome, Texas
That's what I have assumed. The dual talon I recently purchased works just fine on 12vdc but does have an internal flasher. It appears to have only six diodes instead of eight though.
 

wilsonbr90

Member
Sep 30, 2013
1,427
Corning, New York
With whelen its either ballast or passive which determined how its wired on the pc board. On a ballast module all the leds are wired in series. A typical module requires 29.6vdc to operate efficiently. A ballast takes the 12vdc and bumps it up to that required voltage. LIN8


A passive module is just that, passive, it requires no external device to modify the voltage supplied. A LIN6 is wired in series and parallel. There are 2 groups of 3 leds with a resistor to reduce the voltage. Each group of leds needs about 11.1vdc. The resistor drops the incoming 13.6vdc down to the 11.1 each group requires.
 

Jarred J.

Lifetime VIP Donor
May 21, 2010
11,580
Shelbyville, TN
roofies?

:postcount:
 
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Mar 23, 2015
63
Valley View, PA
With whelen its either ballast or passive which determined how its wired on the pc board. On a ballast module all the leds are wired in series. A typical module requires 29.6vdc to operate efficiently. A ballast takes the 12vdc and bumps it up to that required voltage. LIN8


A passive module is just that, passive, it requires no external device to modify the voltage supplied. A LIN6 is wired in series and parallel. There are 2 groups of 3 leds with a resistor to reduce the voltage. Each group of leds needs about 11.1vdc. The resistor drops the incoming 13.6vdc down to the 11.1 each group requires.
Question: Would it be feasible to use a resistor to drop the voltage from a ballast to drive a LIN6 head? My thinking is that it's just a matter of figuring out the correct resistance and ensuring you have a resistor capable of handling the current being passed...
 

pdk9

Member
May 26, 2010
3,834
New York & Florida
Another tell tale sign of passive vs ballast talon is that you'll hear a (for lack of a better word) "clicking" sound as the light fires (while a passive talon is quiet as it flashes)
 
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