M Prime One wiring guide

This guide will help you in the process of wiring your M Prime One printer. You should have an already assembled printer before starting with this tutorial. If you need help with the assembly, go to our Assembly Guide.

Wiring diagram

You can follow the diagram below to wire your M Prime One. Click on the image to download a PDF printable version.


How to wire the M Prime One

  • Power supply. You have to connect the power supply connector to the RAMPS electronic board screw terminals. Both the power adapter and the RAMPS screw terminals are labeled with positive and negative symbols (black, negative/ground – red, positive), connecting the wires with the wrong polarity will damage your board. After you have finished wiring the board you can plug the power supply to the power connector and start using the printer.
  • Hotend fan. Your fan hotend needs to be working whenever you are printing. To achieve this, connect the fan cables directly to the power supply screw terminal. Positive (red) cable to the positive (+) input and negative (black) cable to the negative (-) input. Wrong polarity can damage the fan.
  • Layer fan. Connect the fan cables to the D9 screw terminal of the board, positive (red) cable to the positive (+) output and negative (black) cable to the negative (-) output. Wrong polarity can damage the fan.
  • Hotend heater. Connect the hotend resistor cables to the D10 screw terminals. Polarity is indifferent.
  • Extruder, X, Y and Z motors. Plug the 4 pin female connector into the board 4 pin male motor connectors, with the orientation from the diagram. If you detect that your motors move in the wrong direction when using the printer for the first time, reverse the connector orientation (with the printer unpowered). The orientation of this connector won’t damage the board or the motor, it will just determine the motor rotation direction.
  • X, Y endstops. Plug the 3 pin female connectors into the endstop inputs, following the board markings: S input (signal, green/yellow/white wire), + (positive, red wire) and – (0V, ground, black wire). Wrong orientation can damage the endstop.
    • X endstop is an X MAX endstop, should be plugged into the connector between the X and Y markings of the board (the second endstop bay starting to count from the side nearest to the board power supply).
    • Y endstop is a Y MIN endstop, should be plugged into the connector marked with an Y (the third endstop bay starting to count from the side nearest to the board power supply).
  • Z probe. The Z probe, or bed leveling probe, is connected as another endstop for the Z axis. Plug it to the Z MIN endstop input, the one marked with a Z (the fifth endstop bay starting to count from the side nearest to the board power supply). The orientation is black cable to the signal (S) input, blue cable to the negative (-) pin and brown cable to the positive (+) pin. Wrong orientation can damage the sensor.

Any problem wiring the M Prime One?

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