I want to buy a RAMPS 1.4 controller board for my arduino mega.

First, I saw that there are 2 inputs for power. one is for 5 amps and the other is for 11 amps. Now, my 12v @ 15 amps power supply has 2 output ports each giving out 15 amps. how would I attach my power supply to the RAMPS board. will anything bad happen if I attach 12v @ 15a to both the ports of the RAMPS input? If this will work I think it will be a

good option (if nothing will happen) because I think my load uses more than 5amps. How would I wire this up?

I already have 4 drivers (not pololu ones) for my steppers which control step and direction and power up the motors (not through RAMPS). I want to make use of what I have so is there any way I can use my drivers with the RAMPS board?

Thank you for your time and help.

Cheers, Mitch.

You can connect both inputs to your supply, just use sufficient wire gauge at about 14awg. The inputs won’t draw more power than they need. At 15 amps though that power supply might be too weak if you have a heated bed. Wire this up by connecting the - or minus side of the board to the minus or - side of the power. With the positive side, connect the + side of the board to the + side of the power supply.

If your drivers are pololu compatible they can be plugged right into the board, just don’t get the polarity reversed. Otherwise you will need to do some engineering work to patch the two together.

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thank you for the answer on power. For my drivers, how do I know if they are pololu compatible? They are not pololu ones. I’m using the L298n driverboard connected to a L297 to control the step and direction of each motor. Like I said, the motors are powered up through the driver boards and don’t need to be powered up through RAMPS. Now, how do I wire these drivers (which only need 2 inputs, step and dir.) to the RAMPS board?

Thanks a lot, Mitch

You are going to have to do some engineering work to get the two to work together. I’ve never used those drivers before. Here is the datasheet https://www.pololu.com/file/download/A4988.pdf?file\_id=0J450 to get you started.

Its for the polulu drivers since they are what the ramps board is designed for so at least you know what outputs you are dealing with.

I don’t think you will have any issues with the PS for normal 12v application as long as the entire system doesn’t try to pull more wattage than what your PS can deliver.

I think you are going to run into issues with the separate driver config you are wanting to pull together. The problem will likely be that the signal durations from the Ramps board is far too short for your drivers. To date, this link is the only separate driver that I know of that will consistently work with the RAMPS setup. It’s designed to work with up to 48v to power your bigger steppers as well as the Nema17. I’m currently powering a Nema23 with it on my 3D printer at 24V. The website has some great reading that will help you understand what you are trying to do in great depth. Hope it helps!