my dog's Frisbee launcher
18volt to 14volt step down?
Hi guys, I have an old 12volt Night Sun and I'm build a 14volt LED light.(Achesalot's - fantastic light)
the thing is I work construction and I have lots of 18 Volt batteries and chargers on hand. So I was wondering if I can step down a 18volt battery to 14volts or should I just cough up the cash for new 14volt batteries and a charger? If this can be done...tips or links anyone?
BTW...I was planing on Overvolting the 12 volt Night Sun at 14 volts
...a wiggle theres a way
There are a few ways you can do this
you could get a step down transformer that would take 18in and put ~14volts out
you could also do it with a pot
or you could simply use resistors and make it drop that way just make sure that you get the proper wattage depending on how many amps your application is going to be drawing that way you don't burn them(resistors) out
They do have voltage regulators but to my knowledge they do not have any 14vdc ones (if i am incorrect someone let me know) they have 5vd, 12vdc, and a handful of others
if it was me i would go the transformer route if your settled on using an 18volt pack other wise just get a 14volt one because it maybe easier than having to fabricate a board
A buck converter like the bflex from Taskled.com will do the job perfectly and give you a whole rack of functions to the light. Most importantly it will regulate the current to the led's ensuring a consistant brightness (you set the level), it will also allow multiple brightness levels, temperature regulation, strobe + much more
Hope this helps
Sorry, my old response did not make sense!
Use a buck converter!
If you use the Buck Puck DC-DC voltage converter, it will take up to 32V and give you the correct output amps and voltage:
Originally Posted by befoot
The bFlex takes up to 20 V input:
Deal Extreme offers a cheap driver, but I think the input is limited to about 6 volts:
Sandwich Shoppe's offerings won't take input above 12 V:
A driver is the way to go for LEDs because they are difficult to run well using a resistor. The current draw of an LED changes sharply with very small voltage changes. Plus putting a resistor in line with the LED wastes some of the battery energy.
Note that Sandwich Shoppe, LEDSupply, and TaskLED offer boost converters too. That would make a 12V battery run a 14 volt string of LEDs. But boost converters are more delicate and may require heat sinking. Or they may not offer enough power output. Maybe not impossible, but more difficult.
my dog's Frisbee launcher
Originally Posted by iggs
In the LED system, I'm using a BuckPuck "3023-D-N-1000 Wired, 1000mA Output, DC Powered" from ledsupply.com
so looks like I'm good go to go.
Walt...thanks for all the info and links big help.
I think I will just retire the 12volt Night Sun
and make a 2nd LED light for the bars
more light and longer run times.
thanks...you guys just save me a bunch of cash on batteries
Last edited by befoot; 12-21-2007 at 10:59 AM.
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