Powering my three steppermotors + arduino

I’m building a small setup with three stepper motors controlled by the Arduino. I use EasyDrivers to control them one at the time. They take power from an +/-12v supply I have. I have wired the inputs of the EasyDrivers to get 24v from that supply. I don’t think the supply is powerful enough to power all three at the same time though so I have have the drivers sleep when I don’t use them with an output each from the Arduino.

Everything works great except when I draw 12v from the supply to power the Arduino VIN. Then the drivers just flashes when I try to boot up. When I power the arduino from USB everything is working fine.

I thought it might be a problem that the Arduino sleep outputs where floating at boot so I added 5.6k pull down resistors to them but to no help.

The power supply is an Traco Power TXL 060-0522TI Three channel power supply
V1: 5v (7.0A)
V2: 12v (3.5A)
V3: -12v (1.0A)

Drivers take power from V2 and V3 (24V). I tried to take power to the arduino from V2 and G2. G2 and G3 are bridged.

The Arduino is an old Duemilanove ATmega328.

I understand that this information might not be enough for you to help me but I would be glad for any kind of input right now. Thanks!

I tried to power the arduino and the motors from V2 and G2 only. The worked like a charm so I might stick with it. I still don't understand what went wrong with the other setup.

I still don't understand what went wrong with the other setup.

As you have not described it clearly I can't comment. Make a drawing showing all the connections clearly and post a phot of the drawing.

You have not posted links to the datasheets for your stepper motors.

An Easydriver has a max current of 750mA IIRC so a 12v 3amp power supply should be adequate for 3 of them.