Hi!
It is difficult to see the photos, but do I need female connector to PMDX card?
I've Ordered paralell PCI card to my PC, where I must have female contact.
I bought a printer cable with female and male contact.
If PMDX need female contact, I must have printer cable with female connector at both ends.
What do you use?

See my cable:

Your cable's connectors are correct.

This is the PMDX-122 connector:

http://upload.wikimedia.org/wikipedi...ronics-36F.jpg

See:
http://en.wikipedia.org/wiki/Micro_ribbon

Thanks Gerald
My technical english is not good, so it is difficult to search the Internet for such questions.
So it's good you understand my question.

Svein, I understand your English better than many people who have English as their first language. It is because you try harder to explain in short sentences with simple words.

When I am in a non-English country, I understand instructions much better from from people who try their best to speak a little school english to me, because they speak slowly and say each word clearly. When I am in England, Wales, Scotland, Ireland, America, Zimbabwe and with some people in Asia, they tell me that their home language is "English", but I can hardly understand what they are saying because they talk so fast and use strange accents.

So, no need to apologise for your English - I like it!

I must apologise for not knowing even one word in Swedish, and I have visited your country less than a year ago.

Power supply to PMDX-122
 

I'm not Swedish Gerald, I'm Norwegian. :)
I have a question.
My PMDX-122 has arrived, and I will buy power supply to this.
To make it easy, can I use this??:
http://www.altitec.no/product_info.php?products_id=7009

230VAC-9VAC (not adjustable)
Capacity: 20.0 VA 2.1 A
Is VA and A ok?

Svein,
The 9VAC output is just right for the pmdx. It is more power than needed but will work fine. :) Check page 18 of the pmdx manual for the proper connection points.

Thanks
I buy this I think.

Mr Norway Svein, (sorry), that transformer looks 100%.

The PMDX-125 is scheduled for release in June '09:
http://www.pmdx.com/BreakoutBoards

It looks as if the new pmdx 125;
runs on mains power instead of 9v.
has more accessory relays for router/vacuum/dust collector
http://www.pmdx.com/BreakoutFeatures

I am sure that the PMDX-125 is intended to replace the PMDX-122 in the course of time. Personally, I would only look seriously at the PMDX-125 after it has been on the market for about a year and has been thoroughly de-bugged. By which time there may be other products that are more USB (and proximity switch) friendly.

I would love to see a PMDX-product that is:
- USB
- Mach or Linux(EMC) compatible
- Mains 230 or 115V
- capable of stringing proximity switches in series
- capable of all the standard BOB functions we already have (E-stop, charge pump, couple of relays, etc.)
- small, but not tiny.
- fitted with pluggable connections for quick board swops.

I have a question regarding the PMDX, its not MM related, I have one in my tiny weenie router :) if this is not allowed, please delete this post I fully understand.

I have the pmdx almost fully configured, the only problem Im having is configuring the relay to act on M3, M4 and M5 commands.
I configured Mach3 motor outputs, enabled the spindle (step & dir pins set to 1 and step & dir port set to 1) also set the relays for direction both 1 in the spindle setup tab.

The problem I have is:
I can enable the spindle (metabo grinder) by issuing M3 but I cannot stop the spindle by issuing M5, the only command that stops it is M4. How can I stop it using M5???

Thanks!!

found the solution :) I confused things and mixed spindle with relay, what I needed to do was to enable output #1 and configure the relay settings for CW and CCW in the spindle setup tab.

E-stop and outputs
 

I think I know the answer allready but I would like to have a confirmation to be sure.

On the PMDX website I found this for the PMDX-122
"Inhibits outputs when E-Stop or Fault inputs are asserted"

If the E-stop is activated on the PMDX-122 will this than also deactivate all the outputs?
If I have a contactor coil connected to the relay on the PMDX-122 will this contactor open if the E-stop is activated?

The E-Stop controls the on-board relay. Here is some information from Section 3.4.2.1. (page 17) of the PMDX-122 manual:

When either (or both) the E-Stop (active high) or Fault (active low) inputs are asserted, the following actions take place:
• The ACK bit in the PC’s status register reads as a “1”
• The LED labeled “E-Stop active” (reference designator DS10, near J6) is “on”.
• The LED labeled “Outputs Enabled when lit” (reference designator DS1, near the center of the board) is “off”
• The control outputs are tri-stated with a weak (10K ohm) pull-down
• The relay is de-energized
• The data bus outputs may be tri-stated with a 2.2K ohm pull-up, depending on the setting of jumpers JP2 (see section 3.1.3) and JP5 (see section 3.1.4)

Mike,

Thanks for pointing this out. I must have overlooked it in the manual.

"The control outputs are tri-stated with a weak (10K ohm) pull-down" Does this mean that all the other outputs on J8 (non relay) are also deactivated?

Bart,

Figure 4 on page 9 shows that the step/direction signals are deactivated whenever the E-Stop switch is opened.

Figure 5 on page 12 shows that the signals going to J8 are also deactivated when the E-Stop switch is opened.

The 10k resistors will still pull the signal to a LOW level, but at only 0.5mA. SOME input circuits driven by J8's outputs might work at 0.5mA. MOST TTL type circuits need a minimum of 4mA to work properly. Because I normally add opto-isolators, to all outputs, the E-Stop would work perfectly for my use. Opto-isolators require about 10mA of current to turn on the internal L.E.D.

Hi anyone printed circuit board design interface for stepper motor controler is?

NGH,
The pmdx is a manufactured product, not a DIY type kit or available as plans. If you are interested in building your own, www.pminmo.com has some free plans that are available.

witch bob
 

I would like to know my most of you the PMD over the CandCNC?

Mac

Because we have good experience with it, no complaints, good docs, good support, good price.

Mike,

Thanks for the info

Gerald you had mentioned the PMDX-125 awhile back and I was just checking it out. Does anyone know of any mechmate builders/members with it running? Looks very promising! Still as you said, would be good to wait and see, let them debug everything. Don't like being a guinea pig while cutting!

Under the assumption that the board had been around for a while now, I got the PMDX-125 Gecko 203v bundle from PMD and am now assembling a kitchen table experiment (waiting for motors to arrive). Hoping some one has by now tread this path and is willing to share some tips.

I'm not too stressed about frying the Geckos (internally fused), and think I can hook up the BOB (even though it is 240v at one end - more than I like in live circuits), but I'd love some pointers on wiring the estop and Gecko fault detection and, especially, some of the silly things to avoid with this particular setup.

PS one of the nice things is that the parallel port ground and output ground are ( optically? wtm) separated

A reversed supply polarity still fries them, fuse or not, I am told.....

The 203's are pretty indestructible, reverse polarity will fry the internal fuse (a 15A part), replacement is bit of pain if you have mounted them in the enclosure already. Spare fuses are available from Gecko or Digikey, I don't have the part number handy.
Greg

See this post on the Gecko yahoo forum, where a G203 owner sent it in for repair and got warned that reversed polarity can damage the drive.

Following on from CNCB's post

Has anyone tried these yet as I am about to place an order for BOB and drivers.

All help and recomendations greatly appreciated.

Cheers
Peter

I purchased one and I'm on my way of building the control box, I already built a control box with the 122 (not mechmate related)
Most of the help you will find here in the forum is for the 122, if you feel confident about interpreting the manual I would go 125, otherwise 122.

Pete, almost all BOB of different make using parallel port can be use. You just need to do enough research...

The main function of a Break-Out-Board is to amplify (and protect) the parallel port signals. I use the PMDX-122. It is an excellent board, but there is no reason that you couldn't build your own, if buget is a main consideration and time is not a factor. A single chip can handle all the step and direction signals for a 4-motor machine. Another chip can handle all the input signals and a third chip can handle the output signals.

The Geckodrive G201, the G201X, the G202 and G203v stepper drivers (most commonly used) all have built in opto-isolation. You would need to add opto-isolation to the input signals and the other output signals, but each 4N2x chip costs about $0.25 each. Add a wall-wart type 9VDC transformer and an on-board 7805 voltage regulator and you would have your own break-out-board.

Building wire-wrapped boards is no longer "fun" for me. I either design boards and then have the boards made (at several hundred dollars for the inital prototype) or I buy ready-build boards (like the PMDX-122 for about $90). But, if you're in for a little design work and a little excitement, build your own. For some, it is part of the experience of building a machine.

If you can design PCB, you can also cut out PCB with MM... or wash your own PCB with conventional method.

Hi Mike,
I had to look up opto-isloation and I found it is a way of transmitting a signal while keeping circuits electrically separated.

I remember there were discussions about the computer ground needing to be separate, so I guess this is the reason the PMDX125 the parallel port ground and output ground are alledgedly optically separated. I'm guessing then that I need to keep the parallel cable isolated from the case if I earth the BOB to the case?

The opto-insolator is use to as the name implies, isolate the source & load, in this case the signal from the PC to the driver in the event of overloading or short circuits... etc. not really about the grounding...

Red,
Ken is right about opto-isolators. Their purpose is to keep the electrical noise that is generated outside the control box from entering the control box and messing with your computer.

It is good practice to ground ALL D.C. signals to a common ground lug, including those that are opto-isolated.

An opto-isolator is an inexpensive device that is commonly used to translate different voltages. For example, I use 12VDC proximity sensors. One side of the opto-isolator is connected to the 12V equipment. The other side of the opto-isolator is connected to the 5V controller side. Only light passes between the 12V and the 5V devices. (That's the 'opto' in opto-isolator.)

Opto-isolators are also commonly used to isolate any signal outside a process control computer's box from the process control computer's circuits, even when the voltages are the same. The cables that connect the control box to the machine sometimes act like antennas and collect all kinds of noisy garbage. Putting an opto-isolator between the inside world and the outside world keeps the 'garbage' out. (Sorry for the metaphor, I know that Gerald's livelyhood depends on 'garbage', but electrical 'garbage' is really nasty stuff.)

Because opto-isolators are usually slow to change state (1 to 10 milliseconds), fast acting electrical noise is too short in duration to activate the signal. Also, because the input L.E.D. inside an opto-isolator requires current to 'turn on', most noise lacks the 5mA to 10mA required to light up the L.E.D.

On my Shopbot, when I installed opto-isolators on the input lines, ALL of the communication errors disappeared. The parts cost less than $10. The result was priceless.

My students are back at uni this week with a ton of learning ahead of them ... I know how they feel!
Thanks for the clear explanation. I have a much better handle on where to apply opto-isolators now.

correct color wire
 

Hi i need of your suggestion, i have this stepper motore nema 34 there are 8 wire, what are the correct 4 wire color for gecko g203v and where i have to connect to geckos ? For example yellow to phase A ect. thanks

i forgot to upload pictures sorry

The M1343020 motor has eight leads, which means that it has four coils. Coil A1 has the Red and the Yellow leads. Coil A2 has the Blue and the Black leads. Coil B1 has the White and the Orange leads. Coil B2 has the Brown and the Green leads.

To wire the motor half-coil, connect the Red wire to terminal 3 on the G203v (Coil A). Connect the Yellow wire to terminal 4 (Coil /A). Connect the White wire to terminal 5 (Coil B). Connect the Orange wire to terminal 6 (Coil /B).

To wire the motor bipolar parallel, connect the Red wire and the Blue wire to terminal 3. Connect the Yellow wire and the Black wire to terminal 4. Connect the White wire and the Brown wire to terminal 5. Connect the Orange wire and the Green wire to terminal 6.

The motor has 1.5mH inductance per coil, so I would use a 35VDC power supply.

The motor is rated 5.6A, but it doesn't say whether that rating is for unipolar or bipolar parallel. I'm guessing bipolar parallel. You would use up to a 188k current limiting resistor. For half-coil (if I'm correct about current drawn by the motor), the motor would draw about 4A, so you would use up to a 62k resistor. Watch the motor's temperature. If the motor gets too hot, use a resistor with a LOWER value.