Hey, I'm doing a project with my rc car, I'm controlling the two dc-motors with my arduino motor shield, which runs fine when i have it plugged into my computer. But when I connect batteries to it the motor shield gets really hot, I connect one 9V to the powerjack on the arduino uno board and then I connect 4 x 1.5V to the VIN and GND of the motor shield. I'm not very good with voltage, amphere and so forth..but wouldnt that be 15V going straight to the motor shield? It says on the discription that the VIN of the motor shield can at most get 18V. How can i figure out how much voltage I can put in without hurting both microcontrollers? Do I have to supply both the microcontrollers for it to work or is it enough with just the motor shield (the code on the uno board wont get any power?) ?
To avoid possible damage to the Arduino board on which the shield is mounted, we reccomend using an external power supply that provides a voltage between 7 and 12V. If your motor require more than 9V we recommend that you separate the power lines of the shield and the Arduino board on which the shield is mounted. This is possible by cutting the "Vin Connect" jumper placed on the back side of the shield. The absolute limit for the Vin at the screw terminals is 18V.
It works good with just one powersupply to the motor shield VIN and GND (6V right now)...the engine at the back which is controlling forward and backward movements works going forward, but not backwards. When I have the arduino connected to my computer, it works perfect; back, forward, left, right. If i use more voltage, would it go backward aswell? Or is it something else going on that i have missed..