Motors not responding

Hi guy and girls

Let me say that I'm new to this forum and new to 3d printing.

Let me also say sorry if this has been covered many times.

I have just finished building my 3d printer (reprap prusa mendel)
I'm using RAMPS 1.4 with a taurino power (instead of Arduino mega)

I've uploaded the firmware and sorted the driver files. When I connect
to pronterface it recognises the printer but I can't move the motors. The motors
are Nema 17s that came prewired. They have 4 wires wired in 2 pairs and are
wired correctly (as far as I can tell)

There is 12.3 volts going to the motors (tested at the motor connection)

The motors aren't making any noise.

The endstops work. (Tested with command M119 three times pressing each switch)

The heated bed works and the hot end heats up.

But all 5 motors make no noise except when printer is turned on

This is my problem. Can someone please help I'm soooooo close!!!!

The only problem I can think is faulty stepper drivers. Anyone have a place I can start.
I'm lost

Thanks

Lee

Please help!!!

Quote
Leesprinter
But all 5 motors make no noise except when printer is turned on

The motors shouldn't make any noise when the printer is off! Perhaps you can clarify this a little.

What interface are you using to control your printer (eg. pronterface)? What happens if you press the x or y home button? My shot in the dark guess is that you aren't homed and your firmware is expecting limit switches that aren't attached and may be flagged, which wouldn't allow your motors to move either direction.

The first thing I would do is verify that you have wired the steppers correctly. It sounds a bit like you might have your pairs crossed. Take a look here: [reprap.org] for the procedure on identifying the pairs of wires for each coil. With RAMPS, each wire should be adjacent to its mate. Also explained here: [groups.google.com]

The motors make a noise for around a second AS the printer is turned on

I use pronterface. The end stops (when command M119 is entered) show they are all low (L) then when pressed they show up as high (H)
I tested this on all the end stops.

Motors pairs are all ok. Tested with multimeter.

I think it may be the drivers. Unless there's something else I'm missing.

Marlin firmware, for instance, is made to not only accept home switches, but also limit switches. Depending on your firmware configuration, not attaching limit switches can prevent your steppers from moving in the "positive" direction. Unhomed motors will also not move in the "negative" direction. Hence my suggestion. So if you haven't tried homing yet, I would start there. Then I would move to the trim pots on the stepper drivers.

If your motors came pre-wired, it's unlikely that the distributor would have screwed up all of the wirings.