Arduino serial monitor external power

Hello,

Can I safely connect Arduino to my PC using the USB port and connect to an external power power source (6AA Batteries) simultaneously? Will it destroy my Arduino?

I need to use the Serial Monitor screen to receive the sensors values continuously. As the overall circuit might draw more than 500 mA it may overload the USB. What I found while searching is once the external voltage is more than 6.6V, Arduino automatically switches from USB to external supply. It means that USB supply will be cut off and the batteries will power the Arduino. My question is, when the USB Power is cut, will the sensor data reach the Arduino's Serial Port Monitor or the data will also stop flowing?

In Short I want 6AA Batteries to Power Arduino, sensors etc and USB connected to PC to monitor the Sensor Data.

Thanks,
Laram

That will work fine

When changing to the USB supply or vice versa it will reset the USB port and "may" cause a very short interruption to your sensor data.

Other than that there is no issue using both supplies at the same time as the Arduino will simply swap to the preferred supply.