RAMPS (w. Marlin) won't move or heat with new extruder

Hi,

tl;dr:

- no motor movement
- no heater
- but temp-data
-> how can I test if RAMP-Shield is fried?


last weekend I upgraded my Mendel to 1.75mm filament. So I added a new Extruder and a new HotEnd (Budaschnozzle).

After everything was back together I heated the machine up (via pronterface) and started test extruding a bit. Seem to work ok.
While slic3r was slicing a model I started cleaning up my workspace after which nothing worked anymore.

So the current situation is as follow:

- connection to RAMPS works perfectly
- Temp-Sensor data gets transmitted and is correct.
- no motor movement, not even a stutter
- no heating

what is baffling me is that the heater doesn't work as well, if only the motor wouldn't move I would have guessed I somehow fried my stepper controllers but with the heater dead too I guess it has to be the RAMPS-shield, right?

I tried the test-firmware too but to no avail...
is there another way to test if the RAMP-Shield is fried?

Perhaps something involving a multimeter?

Thanks for your Attention

Edited 1 time(s). Last edit at 01/29/2013 07:08AM by mostley.

It sounds as if your higher voltage section of ramps (the 12v/24v part) is not working.

RAMPS when powered only via USB will behave exactly as you describe - everything appears to work, but nothing heats/moves.

I would start by checking your power supply. Is voltage reaching the inputs on the RAMPS board.

-sean

Edit - I doubt your RAMPS shield is fried, since it is very modular in design. If everything worked except the bed heater, or except the hotend, you might have fried your mosfet. However, if nothing is working, probably a power issue.
If you are using a computer power supply, how are you turning it on - via M80/M81 and connected to RAMPS, or a paperclip in the green line? Could it be this fell out?

Edited 1 time(s). Last edit at 01/29/2013 07:16AM by mitchese.

Hi Sean,

thanks for the quick response.

I tested the Voltage output of my power supply as it reaches the inputs and it shows it's 12V.
I should probably check if the current reaches the mosfets (I guess it uses mosfets...)?
Where can I find them on the board? This thing is more confusing than the london subway system: [reprap.org]

Ok that suprises me!

Next question, if you turn your heated bed or hot end on, do the LEDs light up in the corner of RAMPS board to indicate the hot end/bed is on?

The next suspicion is a blown fuse, though it should be self resetting. If you have a multimeter, then I would test the connections across the end of the RAMPS.

Easier than the confusing subway map is the schematic below. For position, I will describe using this diagram of the components: [reprap.org]

With the RAMPS on the table in front of you, and the power connecter side closest to you, you have six output pins on the left (D10, D9, D8) and four voltage input pins (two for the bed 11A, and two for hot ends and motors, 5A). Behind the four input hookups, you have two yellow large flat squares, on the diagram markd as F1 and F2 - these are your fuses (which should auto reset). We are interested in power getting past F1, since this is what powers the steppers and hot ends.

Use the multimeter to trace the power, first at the connector block (the 12v 5a) then next step is the fuse F1 (is there 12v here?) and finally, try one of the stepper drivers. You should find +12v on one of the pins. Given the row of stepper drivers for XYZ, take the left hand side of pins. The "furthest back" pin of each stepper driver should have 12v on it (so test the furthest back, left hand stepper driver pin)

If it helps, the schematic is here, perhaps easier to read how things are connected together:
[reprap.org]

If you dont have a multimeter, you can make one out of a light bulb and a few pieces of wire. Make sure the light is rated for 12v (most lights in your car are rated for this)

Thanks, I'll try that this evening.

So I just ran some tests and pretty early I noticed a strange behaviour.
When I measure the voltage on the input block coming from my power supply I get 13V but when I plug in the USB into my laptop the voltage slowly drops down to 0.6V and then stays there. When I unplug USB it rises again.
How strange is that?
Does that mean my power supply is busted?

I'm utterly out of my depth now

What exactly are you using for a power supply? Is it a standard computer power supply (ATX) or a special "hobby" power supply with only 12v out?

If it's a standard computer one, what exactly is hooked up to your printer? Is it just one of the four-pin red-black-black-yellow connectors (of which black/yellow are attached), or is it the gigantic motherboard one with 24ish wires going into it?

It almost sounds like your power supply is shutting off when USB power is applied. Try issuing command M80 which is turn power supply on, if your ps has this feature and it's wired up (M81 is off, btw)

My Power Supply is this one:
[www.ebay.de]

it does not support M80/M81 AFAIK

Hmm this one's a toughy

You are corect, no m80/m81 support. Are you somehow able to test the power supply under load that is not RAMPS?

My current guess is either a bad power supply or short in the RAMPS (though I would imagine a short would cause your multimeter to read zero instantly, and not drop off)

If you (disconnect the power) then remove the stepper drivers, same problem still?

ok after a bit of fiddling I found the problem, it seems the connection to the power supply was fried and created a high resistance, somehow the connection heated up and the cable melted into the plastic...
No idea how that could have happened though...

Now that I renewed that connection it seems to work fine.

After retesting everything, I tried to get the X-Axis moving but it now only moves in one direction. Every other axis works.
During the previous testing I upgraded the firmware so I guess it is probably a firmware problem but I can't imagine what would create that effect.
In Pronterface I can click + or - and it will step only in - direction no matter what.

Any Ideas?

What size of cables did you have previously (and what size now?)

If you have a heated bed, you should use at least ("most") 18AWG, and I would suggest something a bit larger in case you want to change to a 24v power supply in the future.

The problem sounds like an endstop issue, check your endstop hookup and your firmware configuration for the endstop. If it moves only in one direction, it is probably the endstop is constantly triggered, so the software thinks you are always sitting at the 0 position on the x axis. From there you can move to the right, but you can't go to negative numbers. You can disable this with the following setting
#define min_software_endstops false //If true, axis won't move to coordinates less than HOME_POS.

though that won't fix your endstop problem!

ah that probably explains it, they aren't 18 AWG. I'll swap'em with thicker ones.

hm not sure if the endstops are at fault here, because they work.
I can run the motor into the endstop and it stops correctly.
Also all the other Axis work fine except the X-Axis.

I tried min_software_endstops false but didn't change the behaviour.

The behaviour isn't that it won't go to negativ.
It does go but in the wrong direction. No Matter which direction I want it to go it always goes negativ.

To rule out the simple things, I would ensure that the wiring is all the same (assuming you have the same motors). Swap the motors between X and Y, and also swap the drivers between X and Y just to try and rule out any defective motors/drivers.

Remember to ALWAYS have the power disconnected when hooking up or removing the stepper motors from the drivers. You can and will fry the driver if you plugin or unplug the motor while it is powered!

The more complicated answer....

Did you solder RAMPS yourself? The reason I ask is the way the arduino signals the motors to move is using essentially two pins.

One sets the direction (if there is +5v there, it goes one direction, if there is 0v it goes the other direction)
One sets the move - for each 5v pulse it will move one step... so hypothetically:
To drive left:
direction: ++++++++++++++++++++++
step: +0+0+0+0+0+0+0+0+0+0 (would move 10 steps to the left)
Right
direction: 0000000000000000000000
step: +0+0+0+0+0+0+0+0+0+0 (would move 10 steps to the right)

If there is a failure of the "direction" pin (let's say it doesn't get hooked up), it will always move in the "right" direction given the above example (I have no idea which way is which, so the fact that yours moves only right doesn't mean the pin isn't hooked up!)

You can test this with your multimeter, I grabbed a screenshot of the RAMPS board here
[imgur.com]

Red highlights the direction and step pins of the X axis (they are the bottom rightmost pins of each driver; x is highlighted in red and where you should test, Y and Z are highlighted in blue for reference). WIth your multimeter connected to a ground, the "dir" pin should change between 0 and 5v depending on the direction you ask.

no the RAMPS is bought. And did work for about half a year before I changed the extruder and started breaking things -.-

I'll try the swapping right away.

so I tried swapping X and Y.

and now the Y-Axis (controlled through X-Axis controlls) has the same problem.

After changing back I changed the stepper controllers, and now it works on all axis O_o

so now every axis is working except for the extruder.

some day this machine is going to be my death...

Really strange the extruder works sometimes. I even was able to start a print but after the first few layer it startet stuttering and it seemed like it didn't have enough juice to pull the filament if I helped it along it went fine but it didn't turn it by itself.

I tried adjusting the poti on the stepper controller but it just increased the volume of the stuttering.