3D Printer is dead, even after changing electronics

Hello,

A few weeks ago, I had some issues with my 3D Printer, which I posted on the forum : [forums.reprap.org]
I now got a new Ramps board, a new Arduino Mega, 5 stepper drivers and a new screen. I wired all together, following some youtube videos. All worked except the motors. I taught I would just have to adjust the screws and then I saw that the screen was becoming darker and darker, then it was off. I checked the power rails, both had 12v. The screen won't go on anymore, the LEDs on the board are off and the drivers aren't getting current anymore. If I remove the drivers, the LEDs turn on and the backlight of the green also, but no text can be seen, even if I turn the variable resistor. Please help me ! I don't know what to do and am really desperated after all this trouble, I need the printer for my electronic projects and can't rebuy a new one

Are you're steppers backward? Also, can your computer see the arduino when you plug in tbe USB?

Start from scratch. Change *one* thing at a time.

Disconnect *everything* from the Arduino. Plug the Arduino into the USB. Is the power LED on? Can your PC see it?

If that works, try it using the 12V supply.

If that works, try connecting the screen.

If that works, try connecting the RAMPS, with nothing connected to the RAMPS.

Connect thermistors & try. Connect heaters and try.

Plug in stepper drivers (make sure they're the right way round) and try.

Plug in X stepper and try. Then Y stepper. Then Z. Then extruder.

Checked or changed the power supply? Checked the cables and fuses? Always part of the equation. Best starting point, anyway.

3D Printers draw a lot of amps sometimes.

Thanks for all your replies !

I can change the Marlin code and change it. From what I saw in the videos, the steppers should be in the right direction (green and black as 1A and 1. I will try your advice frankvdh as soon as possible The power supply wasn't changed yet but I checked the screws on the ramps board : both rails do have 12V. I will also check it.

The arduino might be running on USB power, have you checked if you have the D1 diode installed?

Info on the wiki - [reprap.org]

Edited 1 time(s). Last edit at 11/06/2016 04:05PM by Nprod.

Hello,
I've tested the drivers : they're working fine, I changed the diode on the ramps board and am now powering the Arduino through USB. Now the only issue left : the steppers won't turn when the drivers are in the ramps board, but the drivers do work if I connect them without the ramps, like this : [howtomechatronics.com]

I don't know what to do now

Change the RAMPS? Might be a bad batch, or PSU taking them out.

That's if you are SURE all the drivers are dead, I would test them one at a time, starting with zero current and gradually increasing until the motor starts turning (cautious way).

If all the motor capacitors were blown on the RAMPs, that would explain why the motors don't turn and all the drivers are OK. Ideally you want capacitors on RAMPS with DOUBLE or more of the voltage you are using to drive the motors, so minimum 24V capacitors on a 12V system, as many mFarads as you want to ensure plenty of juice to power coil windings up. Some RAMPs come with capacitors less than 24V, which is not ideal. Having capacitors fitted which can take more than 24V does no harm and may be critically important to upgrade or replace.

If you are using 24V on RAMPs, capacitor values are one of the things you have to beef up on RAMPs, along with track thicknesses and other stuff. Does no harm to beef up and fit over capacity components even if you use 12V - remember, electrical supplies can vary by 10% or more sometimes.