# How to compensate voltage drop on a wire

I'm using a 12v power supply with 12 meter cable ( 0.5mm ) to feed 4 small motors that use around 3A.

My problem is that when I turn all the motors the voltage goes to 7 volts. I need it t stay around 10-12V.

I need to use the power suplly away from the motors 6 to 12 meters.

Any solutions to avoid this voltage drop on the cable?

• Thicker cables. Commented Feb 1, 2017 at 16:02
• any other way?? Commented Feb 1, 2017 at 16:02
• Firstly, paint nice schematic, otherwise it might be flagged. Also, what makes you think it's voltage drop and not too much current drawn from your power supply? Commented Feb 1, 2017 at 16:05
• My power suplly says 11A from the 12V rail. It should work. It was working with 1 meter cable. The problem is that when I put a lot of cable lengh the voltage drops a lot when the motors turn on. Commented Feb 1, 2017 at 16:06
• You say the cable is 0.5mm. Is that the cable diameter? Also, you say the 4 motors use around 3A, is that 3A each for a total of 12A, or 0.75A each for a total of 3A? Please answer both questions. The voltage drop in a cable can be calculated if the current and cable diameter and length are known. Commented Feb 1, 2017 at 16:19