Hi,

I would like to try my stepper motors and nothing seems to respond!

The RAMPS is attached to an Arduino board and connected to a power supply (both 11A and 5A).

I have installed the 3 jumpers under a DRV8825 on the X-axis and connected a stepper motor on the X-axis.

The latest version of Marlin was uploaded without error and I am using a RepRapDiscount FULL GRAPHIC Smart Controller.

On the menu I selected Prepare / Move Axis / Move X / Move 100mm and nothing happens.

I have not connected anything else on the RAMPS yet, that was to test the stepper motors only.

What am I doing wrong?

J3d

Connect an endstop for X and do a G28 X

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[www.bonkers.de]
[merlin-hotend.de]
[www.hackerspace-ffm.de]

I have not received my endstops yet

Can I "bypass" these?

I just borrowed an endstop from a friend and added it

The LED works when I actuate it by hand but the G28 X does nothing

I also plugged in the extruder on E0 with a second DRV8825 and that also does not respond

The hotend heats up as it should but none of the motors works

I checked that the wires of the motors are paired correctly and they are correct

Did you plug the DRV8825 shields correctly?
Reference: http://reprap.org/wiki/DRV8825 and Photo from Wiki

Edited 2 time(s). Last edit at 04/03/2018 04:48PM by Rossos.

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Proud owner and maker of build from scratch FDM 3D printer [forums.reprap.org]

Hi Rossos,

Yes I did plug the DRV8825 correctly, thanks

There seems to be something that prevents the motors to move, perhaps a safety feature?

J3d

Try sending G92 X0 instead of G28 X, just in case your endstops aren't configured right ( can be tested with M119 )

Edited 1 time(s). Last edit at 04/04/2018 02:49AM by o_lampe.

M119 gives:
09:38:13.441 : Reporting endstop status
09:38:13.441 : x_min: open
09:38:13.445 : y_min: open
09:38:13.445 : z_min: open
09:38:13.445 : ok
is it normal?

G92 X0 does nothing to the motors and gives:
09:45:11.897 : X:0.00 Y:0.00 Z:0.00 E:0.00 Count X:7200 Y:0 Z:0
09:45:11.897 : ok

Edited 1 time(s). Last edit at 04/04/2018 03:46AM by J3d.

Please stop trying to diagnose printer issues with the lcd, Its like trying to fix a car with the steering wheel only. You need tools and to look under the bonnet!

Connect up a control interface, preferably pronterface, but cura is also fine

Watch the main console for errors

There are very few safety features that stop X,Y or Z moving, but there are a bunch for E (hotend temp related)
But endstops are an issue
you cant move in the direction if the endstop in the direction is triggered. You also cant move -ve from the 0 location (without homing that is power on position)

If an endstop is triggered and you try to move in that direction the console will be spewing out endstop triggered messages
You can also send a M119 command at the printer which will report the current endstop status


For testing you should use the ramps test firmware
[reprap.org]

This will move all axis back and forward, no safeties no endstop checking.
It also turns the mosfet on and off, so make sure not to have anything plugged into them that will uncontrollably heat up no temperature monitoring either.

Ok you posted mid my reply with more info,..

Endstops are normally triggered or open
open means it can move in that direction so is fine

This leaves power or stepper wiring or driver modules or stepper motors.

You say you have stepper driver in correct way ... but please take a picture and share it so we can check.
Power... the ramp board takes 12v, some people like to put 5v into the 12v 5amp plug... this wont work. (wont damage anything)
steppers, what type of stepper motors, any data sheet?
How did you determine where the coils are?
Did you wire it so one coil is on pins 1 and 2 and the second coil is on pins 3 and 4 of the stepper connector?

Edited 1 time(s). Last edit at 04/04/2018 03:59AM by Dust.

I have installed Repetier-Host now...

These are the stepper motors I have: [www.aliexpress.com]

I used an ohmmeter to check the coils and there is one pair with the red/blue and the other with the green/black wires, connected to 2B/2A and 1A/1B respectively

Is that correct?

Both 5A and 11A on the RAMPS board are connected to 12V, the hotbed and hot end work, the LCD also, only the motors do not move

The stepper drivers DRV8825 are brand new

Have I missed something?

Here is a picture of the stepper driver on the RAMPS board

I don't know if it matters but my RAMPS 1.4 is from Sainsmart

Also you might wanna check this post here: [forums.reprap.org]

Do the motors give a little "kick" when you try moving them with software? If yes: try adjusting the potentiometers.

If not: I believe you are having a hardware issue.
Which can be manufacturing defect, but not limited to:

• RAMPS 1.4
• DRV8825
• Mega2560

You can check RAMPS 1.4 for short-circuiting issues. I found this guy's video on RAMPS pre-flight checks comprehensive: [www.youtube.com] (Spoilers: it's in Russian)

Also, those small aluminium heatsinks on the stepper drivers: the ones that came for my build were sitting and connecting 3 resistors because the chip was sitting lower than the resistors.

Mega2560 on itself is fragile. It can malfunction in weird places, at weird times. Better always to have a couple of those lying around.

All things considered, this can happens to anyone. Even Tom3D during his Dolly build managed to grab a defective Mega2560 board AND RAMPS 1.4 board.

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Proud owner and maker of build from scratch FDM 3D printer [forums.reprap.org]

Failing to see any issues with info provided so far

Have you set the motor current via the variable resistors [reprap.org]

also try the ramps test firmware (a few messages back)

Edited 1 time(s). Last edit at 04/04/2018 06:31AM by Dust.

Quote

also try the ramps test firmware (a few messages back)

I only recommend using the ramps_test for user, who are able to tailor their working Marlin version after running the test. ( or have a known working file at hand)

I had a similar problem which was traced to the current setting on the DRV8825. If the current is too high the driver will shut down. Be aware that the pot needs to be turned clockwise to reduce current (at least on my DRV8825's).

Thanks for your inputs

There must be something wrong with the Arduino and/or the RAMPS and/or the drivers

I therefore gave up using the RAMPS 1.4 and DRV8825 for the moment and borrowed an MKS GEN V1.4 with A4988 from a friend

That worked straight away except for the z-axis

The x-axis, y-axis and extruder are plugged directly on the board but I have 2 motors for the z-axis.

Since there is only one set of pins for the z-axis on the MKS GEN V1.4 I wired the 2 z-axis motors in series and they respond as expected but sometimes one of them does not move while the other one does which is not good at all

Should I use the spare E1 for the second z-axis motor instead?

Or wire the 2 motors in parallel?

Or increase the voltage on the driver? but to what value then?

Why not try the A4988 drivers on the RAMPS 1.4?

Also, since you raised a whole new subject, I can only direct you to yet another explanation by Dust on these very forums here: [forums.reprap.org]
Have a good one!

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Proud owner and maker of build from scratch FDM 3D printer [forums.reprap.org]

I tried the DRV8825s on the MKS GEN V1.4 on the x-axis (which worked with the A4988) and they do not work

Which makes me think that the DRV8825s have been damaged on the RAMPS, therefore I do not want to risk damaging the A4988s on the RAMPS

I also increased the voltage on the pot for the z-axis A4988 from 0.5 (which is was I set for all the drivers) to 0.75 and it has not solved the problem with the z-axis

The solution may be to use E1 for the second z-motor: is the only thing I have to modify in Marlin to uncomment #define Z_DUAL_STEPPER_DRIVERS in Configuration_adv.h?

I believe that I had read something about orienting the DRV8825 -- you cannot use the location of the trim pot, as it's opposite the A4988. Since they're unkeyed, it's possible to install the stepper driver backwards. the DRV8825 is supposed to be compatible with the RAMPS board.

Yes, the DRV8825 must be installed differently, I checked that before plugging them in

I can only assume that they worked originally and have been damaged after installation on the RAMPS

Is there a way to test them on their own, to see what can be salvaged?

I hv problem with heater and thermistor,I hv Bowden v6 hot end.on connecting pronterface noheating up ofextruder heater,error message:heating failed,system stopped,heater ID_0,pls solve my problem.all other devices work ok.all s motor and fan motor of extruded also work ok. l hv not connected endstop and bed heater.pls reply

Quote
mahesh joshi
I hv problem with heater and thermistor,I hv Bowden v6 hot end.on connecting pronterface noheating up ofextruder heater,error message:heating failed,system stopped,heater ID_0,pls solve my problem.all other devices work ok.all s motor and fan motor of extruded also work ok. l hv not connected endstop and bed heater.pls reply

Hi Mahesh, does pronterface display a temperature value other than zero? If not, then the problem lies in the thermistor cable and I suggest measuring the resistance of the thermistor with a multimeter to see what the resistance is at room temperature.

Did you set a thermister type in the firmware? (what firmware are you using anyway?).

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