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By apayne14
Hey All,
I am trying to run five 1.5-3 volt dc motors with an Arduino Red board. My power source is a five volt adapter. It seems that only three of the motors will run sufficiently right now. I am wondering why this is the case? I seem to have no wiring issues. The code for the motors is also sufficient. Does anyone think this is power issue or something different? Thanks, Alan
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By apayne14
I do not have a schematic. I tried to load pics, but the jpg is too large. The power supply is a 5 volt DC plug adapter that attaches to the Arduino redboard.

At 1.5v operation: 4600 rpm no load, 3750 at load
11.53 Torque

At 3 v operation: 9200 rpm no load, 7800 at load
20.0 Torque
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By phalanx
You can use MSPaint to resize jpegs.

So I'm still going to need more details from you. I need the schematic to understand how you have the motors connected and how you are getting 1.5V and 3.0V from your 5V supply. I need more details for your motors (specifically current draw while under load) and details of your power supply to make sure it can keep up with the load you are putting on it.

All of these factors need to play together properly or you end up with erratic operation.

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By TS-Chris
Are you trying to connect your motors directly to your your RedBoard?

Chances are really good that your motors need more current than you're able to pull from a IO pin on the board. It's also not a good idea to drive an inductive load like a motor from a pin.

You could use a transistor or MOSFET to drive your motors from the RedBoard or a driver board made specifically for small DC motors like the SparkFun Motor Driver - Dual TB6612FNG (1A). Each one of the TB6612FNG's can drive two motors so you'd need three of them to drive 5 motors. The hookup guide will show you how they work.