[Update] Testing motors - they hum but don't move

I built the He3D XI3 (http://reprap.org/wiki/XI3) and I want to test the motors. I'm using Pronterface on Linux Mint. I try to move the x-axis I hear the motor buzz but it doesn't actually move. When I try to move the y-axis or z-axis, the motors buzz then begin to make a clicking noise until I click "Motors off".

This is my first build so it's possible that I don't have anything connect properly!

Any help would be greatly appreciated.

Edited 1 time(s). Last edit at 11/19/2015 05:48PM by lurkus.

Ok, I learned about the trimpots. The reprap wiki says that the x and y-axis motors shouldn't make any sound. So I turn the trimpots counterclockwise and they never go silent.

If you keep turning the trimpots counterclockwise will you eventually reach a point where no power is going to the stepper motor? I kept turning and it never seemed to get to that point.

Use a multimeter and set them to around 6.00-.650 volts. Also try changing the feedrate at which them move in the firmware. It might be set to high.

Edited 1 time(s). Last edit at 11/19/2015 09:06PM by Bloodember.

It's possible that the connector on the controller and the stepper wires are not in the right order or one motor phase has to be switched around.
You often see " black-green-blue-red" color scheme ( which is what the controller expects ), but there is no standard between stepper manufacturers.

The stepper motors will always make noise when they move and some controllers with drivers in fast decay mode produce a louder noise when the motors are standing.
So I wouldn't put too much weight on the noise level, but on the Vref/motor current.

The Vref depends on the shunt resistors your driver is using ( 0.05-0.2 ohm are common ). Read more about adjusting Vref here.
-Olaf

Edited 1 time(s). Last edit at 11/20/2015 02:34AM by o_lampe.

Great advice from both of you, thank you!

I checked the voltage from the stepper drivers and they were all WAY too high. I dropped them down to around .600 volts using my multimeter, but that didn't seem to change the behavior.

So I then used the trial & error method of rearranging the stepper wires and found that they were all wrong. I rewired them and the behavior is now a little different. If I move the x-axis 1mm it seems to work. If I move it 10mm, it buzzes a little longer but doesn't actually move. If I try 100m, it buzzes for a lot longer but doesn't move at all.

I feel like this is progress because I'm not getting those weird pulsating noises from the motors anymore. When I give a command, the sound made by the motors seems proportionate to the distance I requested... it's just not moving!

Could this be because I need to lubricate the rods? I don't think that adding grease to the rods will make that big of a difference, but I'm going out tomorrow to pick some up.

Thanks again for the advice!

Disable the steppers and move it by hand. If if moves easily, then the problem is the drivers.

Try plugging the motor into a different driver.

I just built an xi3 also and spent too much time with non-moving motors on "fast move". Did you set the jumpers under the motor drivers of the RAMPS shield card on the Arduino? That was an undocumented step.
...b

Bishop! That's probably it! The kit came with a ziploc full of jumpers but I had no idea what they were for!

How did you set yours?

Edit: NEVER MIND! I had a look at the reference pics and saw that all 3 jumpers were connected, so that's what I tried. And bingo! It's all working!!

Thanks again for all the help, everyone!!

Edited 2 time(s). Last edit at 11/22/2015 01:58PM by lurkus.