Whelen Vertex in series for 24V application?

[SidewaysLS4]

I acquired 2 Whelen Vertex, and would like to use them on a 24V application.  Any recommendations on my thought of wiring these in series to divide the voltage to get it down to the voltage range specs on these LEDs? 

 

[massfirefighter]

http://www.amazon.com/gp/aw/d/B00BWKXTUU/ref=mp_s_a_1_1/187-1532506-0373011?qid=1442860739&sr=8-1&pi=SY200_QL40&keywords=24+to+12+volt+converter&dpPl=1&dpID=51jrwCqcgrL&ref=plSrch

 

[MtnMan]

I acquired 2 Whelen Vertex, and would like to use them on a 24V application.  Any recommendations on my thought of wiring these in series to divide the voltage to get it down to the voltage range specs on these LEDs? 

Creative thinking, but don't try it. For devices to work reliably in series, they have to be identical loads. The fluctuating, unequal load of  flashing LEDs will cause the divided voltage to swing up and down. A 24V to 12V converter is the right way to do it.

 

[SidewaysLS4]

Yeah, thanks for that.  Just did some measurements and it seems these range from around 700 ohm to 13 ohm depending on state...don't think that would work well as a divider, lol.  I guess I will have to do a regulator. 

Anyone (accidentally) see if Whelen is conservative in their specs?  I'd love for these to be like Axixtech stuff that can go up to 30V...but don't want to test it out myself

 

[Steve0625]

You could build a simple voltage divider. Take two 1,000 ohm resistors, connect them in series from your 24vdc source to ground. The connection in the middle between the two resistors will be exactly half of the source voltage. By varying the value of the resistors, you can get any voltage desired from 24 on down. I'd use 5 or 10 watt resistors for this application. More info is all over the net. Here's a decent one: http://m.dummies.com/how-to/content/electronics-projects-how-to-divide-voltage-with-re.html

 

[SidewaysLS4]

You could build a simple voltage divider. Take two 1,000 ohm resistors, connect them in series from your 24vdc source to ground. The connection in the middle between the two resistors will be exactly half of the source voltage. By varying the value of the resistors, you can get any voltage desired from 24 on down. I'd use 5 or 10 watt resistors for this application. More info is all over the net. Here's a decent one: http://m.dummies.com/how-to/content/electronics-projects-how-to-divide-voltage-with-re.html

I think you gave me the solution, thanks!

Edit:  Just did some calcs on this...might not work so good with the large input resistive changes in the Vertex.  Looks like I'm back to the regulator, drat.

 

[Steve0625]

I think you gave me the solution, thanks!Edit:  Just did some calcs on this...might not work so good with the large input resistive changes in the Vertex.  Looks like I'm back to the regulator, drat.

Should work. The voltage between the resistors is constant. The Vertexes won't change the available voltage.

 

[Steve0625]

The Vertex is not in series with the resistors. It takes it + from the middle of the two and then goes to ground.

 

[MtnMan]

Should work. The voltage between the resistors is constant. The Vertexes won't change the available voltage.

Unfortunately, no. Mr. Smiley is in parallel with the second resistor, so he changes the voltage divider ratio.

Voltage dividers work well as a source of reference voltage, but as soon as you start drawing appreciable current from the divider, the voltage will change.

 

[SidewaysLS4]

I found a regulator on Ebay which fits what I'm trying to do..$9 delivered.  Cant beat that .  Thanks for the tips guys!