Arduino Powers Off when 5V pin is connected- Can i use External Power

Hi all! Its my first project with arduino and i've found some problems. I've built a cnc machine and i use an arduino uno to controll it. It has 3 stepper motors ,6 limit switches and 2 joysticks. I used a solderless breadboard at the beginning and it worked fine except a minor bug with one of the limit switches(arduino powered down when the switch was activated) so i used a solderable board just in case it was the boards fault . I've connected everything on the board like i have before but now the arduino doesnt power up at all when the 5v pin is connected. I've read some answer from similar topics in the forum but i also have another question . Can i use a 5v external power supply instead of the 5v pin from the arduino ?

please upload motor datasheet so i can suggest external power supply. i am using a servo motors for my cnc project so m using following power supply.

u can use 12v 10A power supply.

Yes, it is possible. Arduino's power is too weak to run higher power consumption. The solution is to use an external power. You can also power the Arduino with it. It is the easiest.
If not and the Arduino will use its own power, then GND must be connected.
Make sure the external power will have the voltage within the limits for both cases.

I already have a power supply for the motors , i got no problem there. I meant if i can use a different power supply to power up the limit switches and drivers, i was thinking like a mobile charger with a 9v output . I will have the arduino connected to a pc the whole time so i dont really have to have a power supply for the arduino, I want to use a power supply for the rest of the equipment.if i connect an external power supply for the "secondary circuit" ( switches etc) do i have to connect anything to the arduino ?

If the motor power supply is on a different branch of the household AC circuit that powers the Arduino (i.e. the computer powering the Arduino), you can have severe ground loop problems.

Make sure that everything is connected to the same branch. A power strip extension will help.

Budvar10:
Yes, it is possible. Arduino’s power is too weak to run higher power consumption. The solution is to use an external power. You can also power the Arduino with it. It is the easiest.
If not and the Arduino will use its own power, then GND must be connected.
Make sure the external power will have the voltage within the limits for both cases.

Well i used a phone charger with a 5V output for the switches and drivers ,connected to GND on arduino as well but it doesnt power up anything . And now the arduino has some issues as well.Could the external supply somehow damage the arduino ? if i have nothing connected i can usually upload with no problem ,sometimes it appears to have a problem and crashes . if i connect everything i cant upload anything and the power supply seems to not be able to power up anything .Can i use regulators and power up everything from the motor supply ? i have a 24v 12a power supply.

Could the external supply somehow damage the arduino ?

Yes, if you have a "ground loop" in the AC wiring. It is a very common problem.