<p><em>Can I connect my setup to my PC using USB when the external power is also on?</em>
As long as you are connecting the external power to the correct pins, yes you can.</p>

<p><em>If i connect the USB while the external power is off, do the motors take power from USB?</em>
No, the motors need an external power supply.</p>

CC BY-SA 3.0
2018-04-12T21:15:48.710Z
2018-04-12T21:15:48.710Z
Hussein Fawzy
<p>I have a RAMPS 1.4 with Arduino Mega 2560 with 2 steppers connected to an external power supply using Polulo stepper drivers. The steppers are for X and Y axis movement. This external power supply is set to 12 volts and power is applied. I have configured the marlin firmware also.</p>

<p>Can I connect my setup to my PC using USB when the external power is also on? If i connect the USB while the external power is off, do the motors take power from USB? Will this will burn my board?</p>

<ramps-1.4>
Using ramps on-load
sandeep kumar
# Using ramps on-load

(Asked by: username_0 on 2018-04-10)

I have a RAMPS 1.4 with Arduino Mega 2560 with 2 steppers connected to an external power supply using Polulo stepper drivers. The steppers are for X and Y axis movement. This external power supply is set to 12 volts and power is applied. I have configured the marlin firmware also.

Can I connect my setup to my PC using USB when the external power is also on? If i connect the USB while the external power is off, do the motors take power from USB? Will this will burn my board?

**Tags:** ramps-1.4

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## 1 answers

### Answer by username_1 on 2018-04-12. Score: 0

*Can I connect my setup to my PC using USB when the external power is also on?*
As long as you are connecting the external power to the correct pins, yes you can.

*If i connect the USB while the external power is off, do the motors take power from USB?*
No, the motors need an external power supply.


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