I am using an Arduino to control some mechanical components in a project I have. It controls a motor, two servos, a valve, and a compressor. When plugged into the computer, everything works fine and perfectly. However, when I power it through the barrel jack using our power supply, some weird things happen. First of all, our servos, which are powered through the Arduino, stop working. All the other components work except for them. Secondly, at the end of the code we have a 5 second delay. Using the computer it works fine. When powered with our supply the delay doesn't seem to happen at all. Any ideas?
I believe that the problem that you are facing is lack of power. It is likely that your power source cannot supply enough current or voltage to power the equipment AND the arduino. Try to get a power supply that has more amps.
i agree with majenko, maybe you know how to fix it but if you do not know here is a site with good information to make you're own 5 volt Regulated source.
sorry for my bad english and good luck. :D
I had a similar problem recently while powering a servo with a Arduino. It did turn out to be power, our Arduino could only supply about 500ma and with sufficient speed or torque on the servo (a lot of times just the boot sequence) we would it the 500ma at peak, the effect however was baffling at first because when we hit the peak current the Arduino would reboot, this could account for you extra delay at the end.
For us the solution was simple bypass the Arduino when supplying current to the servos, in our case it as a 5v battery, you would probably need to drop the 12v to 6v in your case.