Motors do not move after initial setting up - Mach setups

[fabrica]

The wiring is done and for the last three hours we have been playing around with the mach3 software get the settings correct.

Maybe we still have not got the pins and other things configured properly. When we try to jog with the sofware the motors do not move. No voltage is developed at the outputs of the steppers drivers.

[Gerald_D]

I think it took me 3 days.......
I started on the kitchen table with one motor and one gecko - after that I built the gantries and cars.

A big problem for me was to understand what the E-stop does and how to "reset" the Mach main screen. Nothing will move while the reset button on the bottom left of the screen is flashing red - it must be only green.

[Gerald_D]

To see if Mach is working, you do not need the Gecko's and the steppers. You can just look at the PMDX board. There are LED's that will flash where the gecko wires are connected, when the step/direction pulses are received correctly.

The PMDX looks like a discotech when everything is working right.

[fabrica]

Ok Gerald maybe I made a mistake by during the process of posting.

This is what i wanted to inform you in the earlier post.

" Gerald Finally I got the motors to move (of course with racks detached from the pinions). What i did to overcome the situ was to switch the jumper settings on JP2. From the original pin connections of 2 to 3 I changed to 1 to 2. This made the PMDX card LED's to light up and the motors to move.

By doing this I have disabled the E-stops, Fault and charge pump circuits. After doing this change I never expected the E-stop to work. But it still did work. What could be the reason for this?

Another reason why I did this change was because I suspected (after reading your earlier mail) that the e-stop settings are a tricky issue. Once I sort out the other matters I could get back to this problem later. The charge pump was also enabled through mach 3 settings.

After changing jumper settings all 4 motors started to turn, other that one motor fixed to X axis (A axis, slave of X).

At the driver point I changed the wire connections (switched the wires connected to non working driver to to the driver which was working) and the non working motor started to work. We could suspect two things. Either the stepper driver is playing up or the Output circuit of the PMDX card which connects the faulty driver board is not working. At this point we called it a day and wound up operatins since it was 8.00 pm in the night.

One more thing which I observed in the suspected stepper driver unit was the the LED in that was glowing much more brightly than the other drivers which were working normally.

Gerald Can a stepper drive be repaired if it is faulty?. Anyway I have one spare driver board in stock.

[Brian_B]

fabrica,

The Gecko website has a nice "Stepper Motor Basics" page that will walk you through the theory and hookup. Go to: http://www.geckodrive.com/photos/Step_motor_basics.pdf

There are many similar pages available online as well. Another is:

http://www.rmsmotion.com/resources/step_basics_v1_0.pdf

Brian

[fabrica]

Brian, Thanks for your input. But how does the info provided by these links relate the issues that I have raised in my earleir mail.

The first issue which I raised was when I disabled the E-Stop (through jumper settings) to get the motors to turn how come the E-stop is still working.

The second issue was the problems that I am encountering with the Gecko drivers (only suspected not yet convicted).

[Gerald_D]

WELL DONE! You achieved in one day what took me about 3 days http://www.mechmate.com/Forum/clipart/happy.gif

In Config > Ports & Pins > Input Signals scroll down to the line EStop and look in the column "Active Low" change from green to red, or vice versa to get the e-stop to work correctly.

The driver LED's are not equally bright - I don't think that this indicates a fault. (Gecko will replace a faulty driver for free, but you have to arrange the transport). I am guessing you have a Mach ports&pins error, so I suggest you swap motors at the PMDX to see what happens.

[fabrica]

Ok I will swap motors at the PMDX point to see where things have gone wrong and post you the results by tomorrow morning before you start work (we are 2.5 hrs ahead of you). Now it's almost 11.30 pm over here. It's time for me to hit the deck after very strenuous and ejoyable day's of work.

[fabrica]

Checked the motors. It was was the driver which was faulty. Replaced the driver with new driver motor worked perfectly.From CNCZOne found a simiple way to check Gecko's. Info given below.

"Quick test. Disconnect the main connector, get a multimeter and set it to Ohms. Connect a probe to COMMON, then measure COMMON to STEP, then COMMON to DIRECTION. The reading you want to see is 1.2K give or take 5%. Get that and the drive is probably OK".

I followed the procedure and did the checking. Both readings were perfect. For the monet I will go ahead with the new Gecko and see what could be done with older unit later.

[fabrica]

I have encountered two more problems today morning while setting up the machine.

One motor on the x drive is getting too heated. The other issue is that the Z axis motor is rotating only in one direction.

[Gerald_D]

Hot motor: Check your resistor that you fitted to the Gecko. Do not trust your ability to read the colours on the resistor, use an ohm-meter to measure it. Measure all the resistors - if this one is different then that is the cause. If it is the same, then there is a setting under the cover of the gecko which must be checked.

Direction: On the PMDX there is a LED for each motor which shows the direction. Is this LED indicating the direction change correctly? (compare to the behaviour on the other motors) If it is, then check the wire connections between the PMDX and the gecko.

Strange gecko behaviour: nearly a year ago gecko had problems with bad connectors. They changed the supplier. Maybe you have one of these. The connector does not like to be removed many times from the gecko.

[fabrica]

The problem with motor heating was sorted. After changing the drivers we had not inserted the resistor on to the new driver.

The problem with the Z axis motor still exists. It is only moving in one direction. When we try to move it in the other direction it only makes a noise but the shaft does not turn.

One more thing that I observed was that when pressing the e-stop button, the LED on the PMDX card which is situated just above the output connectors lights up. This is very unusual.

[fabrica]

With regards to the lights on PMDX. For X,Y and A outputs the light tuns on when moving in one direction and does not light up when moving in the other direction. On the Z outputs the light turns on in one direction but is very faint.

[Gerald_D]

Is the Z-motor still disconnected from the rack? What happens if you swap that motor's wires to another gecko?

Your e-stop logic, with PMDX jumpers and Mach ports and pins settings is still mixed up. I have little experience to fix this because ours worked right and then I left it alone for more than a year. The only thing I can suggest is to put the jumpers as per the drawing above, put a temporary wire across the e-stop contacts (like the pmdx was supplied - J6 across e-stop and GND), and then play with the Mach settings until it works correctly. When you put the motors against the racks, then you can put the E-stop switch in that jumper wire at J6.

[Gerald_D]

Regarding the faint LED for the Z: Disconnect the wire below the LED (the one going to the Gecko) and see if it is still faint - maybe there is a short in that wire....

[fabrica]

The Z axis problem was sorted out, it had been a software issue (mach3).

I am starting to enjoy this Gerald.

[Gerald_D]

Can I relax now? http://www.mechmate.com/Forum/clipart/happy.gif

Would you agree now that it would be good to have the 4 motors on the kitchen table at home first? Do this in parallel to the steel construction....

Now you can tell us your secret? I am sure you have already connected the motors to the racks and made the beast move....http://www.mechmate.com/Forum/clipart/proud.gif

[fabrica]

The machine is moving well without any problems. Setting up the home point (0,0) and the limits.

Please educate me on the the rate of accelaration that a normal mechmate should run at. We increased acceleration once and the gantry jumped off the rails. May be we should increase the tension of the springs further. We have kept it at the lowest point.