MY ULTIMATE PROBLEM with the psu went something like this: My power supply was powering a circuit as shown here.
http://bayimg.com/mAoGkAAff
For some reason,when I tried to power the Aruino via the Vin pin and 12V from the power supply,the 'current-limiting' action started-> I turned the right current knob a little and eventually fried my bluetooth module.
I presume this happened because the voltage regulator inside the Arduino did not drop the voltage to 3.3V. The 3.3V was feeding my bluetooth module then. What's going wrong here?