Movement, Logo and CUTTING between the beer cans #39 - Wroclaw, Poland

[jhiggins7]

Martin,

Great looking box.

I notice that you have the fan vented to the outside. The Forum recommends that the box not be vented. The fan just moves the air around in the box and the metal sides of the box conduct the heat out of the box.

However, several builders have vented the box, but they use a filter so that the dust and dirt associated with the MechMate, in operation, does not get into the box.

Regards,
John

[martin77pl]

Hello John,
I will go for vented box probably. I am gonna use a filter. The filter to be used to cover those little holes I drilled. So cooler air will be sucked in and I am thinking of another filter in the bottom fo the box. The bottom filter to let the air out so there is gonna be air circulation. Or maybe as you pointed out I could tape them holes, cover them and let the in-box circulation to do the work.

Thank you for your reply
All the best Martin

[martin77pl]

Hello guys, I got to a point where I am faced with wiring my motors. I chose Oriental Motors. I received four PK296AE-SG7.2 they have eight wires. As far as I understand I am supposed to use only four of them to get half coil connection. Which four of them do I use? What happens to the other four? Am I supposed to isolate them?

[Gerald D]

Use black, yellow, red, white and insulate all the others.

[martin77pl]

I have a question concerning printer cable. Is it possible to use one of them showing in the photo? I am asking because I used this cable to connect pmdx to my laptop. I failed to have the motors turning. Everything seemed to be ok. The green light on the geckos but still no response with the motors.

[Gerald D]

That is a USB to Parallel converter buit into a cable and it plugs into a USB port of your computer? This type of product will not work with Mach3. Mach3 will not work from a USB port (unless you use a SmoothStepper)

[domino11]

Martin,
That is a USB to parallel converter. Although they work fine for printers they will not work properly for the BOB and Mach 3. This has been tried by many and nobody has succeeded to my knowledge. Mach needs a real hardware printer port to function properly. Be also very careful when ordering a plug in parallel card for your computer, some are acutally the same as the cable you mentioned on a card. There is a thread here on that subject somewhere.

http://www.mechmate.com/forums/showthread.php?t=1415

Try this one.

Sorry Gerald, you replied while I was searching for the other thread.

[martin77pl]

Thanks guys. I went to the cellar and brought my mother-in-law's old pc. I just tried that and still nothing. Maybe I got it wrong configuring mach3. It is not that easy anyway for the firs time. I do have mach3 trial version maybe this wont work properly. Is there a thread where mach3 configuration is discussed?

[martin77pl]

Ok I found it in cnc motion control software.

[Gerald D]

The trial Mach3 is 100% the same installation as the paid Mach3.

With trial Mach3 you are limited to 1000 lines of G-code. Paid Mach3 can handle any length of G-code. This is the only difference between trial and paid Mach3.

[Richards]

Verify that you have correctly set jumper JP-1 on the PMDX-122 board for the Gecko G203v stepper drivers. The G203v drivers use Common GROUND, so you must use the settings found in Figure 2 on page 7 of the manual. (The manual can be confusing because many users assume that the settings for all Gecko stepper drivers use Figure 1 that is found on page 6; however, that jumper setting is for the G201, G202, G210 and G212 stepper drivers. Those stepper drivers all used a Common HIGH signal. Marris changed things when he designed the G203v. There have been several times when I've gotten caught when I've switched the PMDX-122 card between test benches. One of my test benches is setup with G202 stepper drivers. The other test benches all use G203v stepper drivers. When I forgot to change the jumper setting, the stepper drivers didn't work. One time I even had the oscilloscope hooked up so that I could look at the signals - then I remembered to switch the jumper.)

[Gerald D]

Motors won't turn after the setting up - PMDX-122 jumpers incorrect

Cannot get motor to turn - Mach Ports & Pins setup

Motors do not move after initial setting up - Mach setups

Upgraded Mach, now the motors won't turn - Different ports/pins for later Mach

[martin77pl]

There is some change in the motor reaction and lights on the geckos. But still nothing close enough to wha it should be. When pressing arrows on the keyboard the motors are buzzing or wibrating. They do not turn just vibrating. I did change the jumper to be grounded for the gecko on the pmdx. There is red light on the gecko together with the green one. Maybe the power is not sufficient enough to power up the motors? When I press tab on the keyboard and there is 100 % slow jog motors buzz. I changed that to 60 % motor started to turn slowly but still vibrating. Any ideas what might be wrong?

[Richards]

How have you connected a power supply to the PMDX-122 card? Page 4 of the PMDX-122 instuction manual lists the three different ways that a power supply can be connected to the board. (In your photo, I don't see anything connected to any of the three power supply inputs - to the USB connector, to the J11 coaxial jack, or to terminals on J8.)

[martin77pl]

I have it connected via usb from a computer. The picture does not show that but chose this way of powering the pmdx.

[Richards]

Let's do some basic trouble-shooting. Check the voltage on the PMDX-122 J5 connector. Verify that you have 5VDC between the +5 and the GND terminals. Then, with your meter connected to the +5VDC terminal on J5, verify that you have 5V when you touch a probe to J1-Common, J2-Common, J3-Common and J4-Common.

The actual voltage may be slightly different, but +4.75V to +5.15V is acceptable for most TTL type circuits.

If the voltage test passes, then you'll need to use an oscilloscope to check the actual pulses being sent to the G203v stepper drivers. All that the PMDX-122 board does, as far as step and direction, is to buffer (amplify) the signals. Whatever signal is sent through the parallel port to the PMDX-122 is buffered and then passed on to the G203v. If you connect the 'scope's ground lead to GND on the PMDX board, and then touch the probe to J1-Step you should see pulses being sent to the G203v. The voltage of the pulses must be at least 2.5V (they will probably be about 5V). The width of the pulse must be at least 2uSec (which you can set in the Motor Tuning section of Mach 3).

At this point, as long as you have a Green light on the G203v stepper driver, pulses sent through the PMDX-122 to the G203v should make the motors turn.

A very crude test can be made my connecting two fresh AA batteries in series (so that you have about 3V). Connect the (-) end of the batteries to the Common on the G203v and then tap the lead from the (+) end of the battery to the Step terminal on the G203v. The pulses will cause the motor to turn. It will take 2,000 taps to make the motor's shaft turn one time, but you will at least be able to verify that the G203v is working.

[martin77pl]

I checked the voltage. It shows 4.9 VDC on the pmdx +5 and ground on J5. I also tried J5 +5 and common on J1 J2 J3 J4 and again it showed 4.9 VDC. I used tuninig settings in mach3 and managed to have the motors turning nice and smoth for 30 seconds or so. Then they stop and the red light appears on the gecko next to green one. The green and the red are lit together. I think it might due to the wire I used for the kitchen project. The trouble shooting page in the gecko user manual there is something abouth not using short circuit. I cut wire which is a meter long and used it to connect the geco and the motor.

[bradm]

Hmm. Two thoughts:

Check this: http://www.mechmate.com/forums/showt...07&postcount=2

And, from the Gecko manual:

ERROR LED: The RED ERROR indicator is lit when:
1) During power-on reset for 1 second when power is first applied to the G203V.
2) While the DISABLE input is active.
3) When there is a short-circuit on any motor output. Momentarily activate the DISABLE input to reset.
4) During over-temperature shutdown. The LED automatically resets when the drive temperature drops.

Obviously it's not case #1. Since you motors did run for 30 seconds, it probably isn't #3.

So I think you should:

A) take a measurement on your disable input pin
B) Double check that issue with GND it the referenced post above.
C) Double check your current set resistor values by measuring them.
D) Double check for a thermal problem. Are your geckos warming up? Are they heatsinked well?

[Richards]

Let's look at the wires from the motors again.

- Have you taped each unused wire so that it cannot short itself to any other wire?

- Are the current limiting resistors about 40K?

- What is the temperature of the G203s (Room temperature, warm or hot)?

- Is anything at all connected to the Disable terminals on the G203s?

Assuming that you've used an extension cable between the G203 and the stepper motor, are the wires electrically insulated from each other?

My G203v drivers are all heatsinked on a large piece of aluminum, but I don't think that even unheatsinked drivers would overhead in 30 seconds from motors that only pull 3A maximum. When I run my PK296B2A-SG3.6 motors, the G203 drivers hardly ever get much above room temperature.

I'm thinking that you have mistakenly miswired the drivers to the motors somehow. If possible, connect a motor directly to the G203.

-Wire the motor's BLACK wire to coil A (Terminal #3).
-Wire the motor's YELLOW wire to coil /A (Terminal #4).
-Wire the motor's RED wire to coil B (Terminal #5).
-Wire the motor's WHITE wire to coil /B (Terminal #6).

[Lex]

Hi Martin,
I had the same problem with my test panel. I checked every wire to the motors for continuity. I found 4 bad crimpings. Fixed them and everything worked! Problem was that only one coil was working making the motors to oscilate. Good luck.

[martin77pl]

Hi everybody, I used your advice and connected motors directly to the gecko. I did it and it turned out to be excelent idea. Well I tried with only one connected and it run smoothly and continously without any interruption. It seems there was a a problem with the wire I used for connecting the motors to the gecko. Anyways, I hope all of them will work fine just like the one I tested. I thank you guys for your advice. It was awesome experience to see the motor turn and change direction without a problem.

[martin77pl]

I have almost everything ready with them control box. My other parts for the mechmate are also waiting. Racks and pinions, bearings from Rick and Superior Bearings. At first I wanted to have the table made form me but now I will venture to build it. Just need to find space for it. It would be quite difficult to find some in the block of flats I live in. Let alone it is on the second floor. I have a question about the E-stop though. I run my power supply on 230V and I read that it is not advised to place any switches on the DC side of the control box. So bearing in mind that high voltage do I wire the E-stop to PMDX using the voltage through that BOB?

[Gerald D]

Martin, can you give us photos inside your control box before we answer the E-stop question? I would like to see the back of the E-stop switch on the door, and the components where you connect the transformer.

[martin77pl]

This is how I got it wired in the control box.

[Gerald D]

Normally the E-stop will have 2 independent switches behind it (your photos show no switches on the E-stop button now). Both those switches will be Normally Closed (NC), for us they will be red, similar to the red and green switches behind your stop/start buttons.

One switch will handle the PMDX - see diagram in this post. See connector J6 at top left.

The other switch will break the mains supply to the transformer, by switching off the contactor. At the control box, this does exactly the same as your red stop button.

[Richards]

Gerald gave an excellent description of connecting an E-stop switch.

It's good to remember that the E-stop on the PMDX-122 board ONLY handles 5V. It SINKS current, meaning that whatever is attached to the E-Stop input must normally be connected to ground. When the E-stop switch is activated, it opens the circuit so that the E-stop input floats HIGH and the PMDX-122 stops all outputs.

So, if you use a two-switch E-stop, as Gerald described, it will be easy to let one switch handle the low voltage/low current required by the PMDX-122 while the other switch handles the high voltage/higher current required by the self-latching circuit that keeps the Contactor energized.

[martin77pl]

HI everybody, it is good to be back. I am happy to show you some more pictures with the progress. The next stage is finished and the table is standing. Before we started with the welding of the actual table frame we decided to practise on the shop table. It is good to have one anyways. Now probably more daunting objective is approaching. There are four rails to be done with the device attached to the grinder. Again I shall practise before I start the jobi.

[sailfl]

Martin,

Your build is looking good. You need to add some color on your machine to brighten the place up.

[martin77pl]

Hmmm, in this particular shabby environment I think shinny yellow instead of blue would do the trick

[bradyaero]

Very nice Martin,

Although you might need more Zubr to hold down the I-Beams!