I need some help with ramps and an external 5v supply for the BLtouch.

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1

I need some help with ramps and an external 5v supply for the BLtouch.

I have a 5v BEC from my RC builds, and think that should do just fine…

I’m planning to plug the input side directly from the 12v supply, and the output positive terminal to the 5v ( middle pin) on the servo rail…

My concern is only the negative terminal from the output side of the BEC… I just leave it unconnected?

2

It’s the same ground, so yes, leave it disconnected.

3

Did you remove D1?

4

@Greg_Nutt No, I did not remove D1, and should not.

I have cut the 5v supply on the USB cable since I need to guarantee the power up sequence of my TMC2130 drivers + I’m using the Re-Arm board on Marlin 2.x, not a Mega.

5

I’ve connected the 5v output to the 5v on the servo rail. I left the negative from the BEC disconnected. I can confirm it works :slight_smile:

6

Having done this myself, I can also confirm it works.