Problem wit12V DC Power Jack to power both Arduion Uno and moterboard

Other Hardware Motors, Mechanics, Power and CNC
1

Dear all,

For controlling four motors I have bought an Arduino uno and a motor board (Multi-motor from robot Power , http://www.robotpower.com/downloads/MultiMoto-v1_6_schematic.pdf). After downloading some code for this setup I tested the code while supplying the motor board with a 9 Volt battery, with Vin jumper connected. This worked fine. However, when I tried the same setup, but using the DC Power Jack(using an adapter from 230 to 12V, so it is supplied by the powergrid) did not work. The check light goes on, but the motors do not seem spin at all, even after changing the speed parameters in the code. Switching back to the 9V battery made it work again. But as the Robot will have to move around for a long period of time(11 hours) - over a limited distance - I would like to power the Arduino and the motor board using only the 12V adapter. Any suggestions?
Thanks for reading and thanks in advance. Also let me know if you need more information

Arthur

2

It is not a good idea to power the Uno with 12V. The on board voltage regulator is very small and tends to overheat and burn out.

To safely run the Uno from a 12V power supply, you need a step down voltage converter to produce 5V and feed that into the 5V pin on the Uno.

Your 12V motor power supply should be able to provide at least twice the maximum current drawn by the motors. Post a link to the motor data sheet or product page.

9V block batteries are for smoke alarms, and are generally useless for Arduino projects.

3

jremington:
9V block batteries are for smoke alarms, and are generally useless for Arduino projects.

Real useless I say...

4

They work fine in smoke alarms.