3-12v adjustable wall wart-1 amp?

robiwon · Post by **robiwon** » Thu Jul 10, 2014 7:59 am

So, I finished my Moebius TOS Cylon Raider. I used two amber LEDs for the headlights and 8 white LEDs for the engines, all wired in series. It's powered by two AAA's under the cockpit canopy. I was thinking however of converting to a wall wart I have, listed above. Would that work, set at 3v, or is the 1 amp to high? Would that 1 amp rating produce magic smoke? LED Calculator say my circuit draws 200mA. I've always been buggered by the mA/amp rating.

brt · Post by **brt** » Thu Jul 10, 2014 3:41 pm

I'm only aware that if your LEDs do not get enough amps/milliamps, that can cause issues. I'm not an expert though. If you have the LEDS to spare, hook up the same number to your 1 amp supply and see what happens, sparing your model.

robiwon · Post by **robiwon** » Fri Jul 11, 2014 8:34 am

Thanks. I was a bit dyslexic yesterday, the circuit is wired in parallel, not series. I always get the names backwards for some reason!

Pat Amaral · Post by **Pat Amaral** » Fri Jul 11, 2014 9:27 am

Wall warts can be finicky animals. The Amp rating labeled on the thing (in
your case, 1 Amp) is what the unit is capable of drawing under its optimum
load. That being said, the current draw your circuit is calculated at is much
lower (200mA). What I've found with most warts is that if you're driving a
circuit at an amperage that's lower than its rating, and it's not a "regulated"
power supply, the voltage supplied by the unit will be higher than its setting
says it should be. That's when you can start having problems. One artifact of
this is that the wart will run hot (temperature-wise).

My recommendation is to try to find a regulated wall wart that matches your
voltage requirement and has a current (Amp) rating closer to what your circuit
needs. They tend to cost a bit more but you'll get much better performance
and it's safer in the long run.