Everything ok, but motors no move ! ! HELP please ! !

[Merchi]

So I just finished mounting all electronical gadgets of my litle machine and it doesnt work
What I have as it follows:

- 3 Geckodrive G203V
- PMDX 126 breakout board
- 134 PMDX board to conect easily the geckos
- Antek Power Supply with 56V and 18A
- 3 nema 34 1850oz / 8A/phase / 3mH/phase (wired up in parallel mode)

I suposse that I have all correctly wired up, but when I try to move any axis the breakout board receives the signal OK but the motors makes like a litle try to move (it sound like a "pop") but finally no moves (it has a holding torque, so I cant move it manually)

The doubts I have are:

1- Each motor needs 8A/phase, but as they told me the gecko just supports 7A so in the end, the power supply wont need at least:
7x3 = 21A ?
What will hapen if I just provide them 18A ? Wont move, they will move slowlier ?
2- Will be a problem if in my electrical installation I just have 10A ?

As it says in the geckodrive page (here) I will try to measure tomorrow those voltages, but I am almost sure that it will be a problem mentioned above.

Some photos of my installation (provisional) :




Thanks for future help

[awerby]

What kind of computer are you hooking this up to? Is it a desktop or a laptop? Are you really getting 5v on the parallel port? Do all the leads on your parallel port cable connect all the way through? Is the parallel port in EPP mode?

While the lack of amperage may cause problems in the future, when you want to run multiple axes simultaneously, I doubt that's the problem right now.

Andrew Werby
ComputerSculpture.com — Home Page for Discount Hardware & Software

[Markwind]

sounds like a software issue
-check for correct step/dir pin assignment in mach 3
-check active high /low

[Merchi]

What kind of computer are you hooking this up to? Is it a desktop or a laptop? Are you really getting 5v on the parallel port? Do all the leads on your parallel port cable connect all the way through? Is the parallel port in EPP mode?

While the lack of amperage may cause problems in the future, when you want to run multiple axes simultaneously, I doubt that's the problem right now.

Andrew Werby
ComputerSculpture.com — Home Page for Discount Hardware & Software

I am running a deskopt PC and I have manually measure ports 2 to 9 directly from PC and with the cable to ensure that was not broken and all of them got 3.3Vdc
And yes, I got EPP mode on the parallel mode

Thanks for help

[Merchi]

sounds like a software issue
-check for correct step/dir pin assignment in mach 3
-check active high /low

I have tryed all pins from 2-9 and with three, two and just with one axis to ensure that it was not an insuficient power case.
What I have noticed is that the board just detects me when I push the axis to one way. If I push the axis to the other way it does nothing.
Finally, I took off the 134 and I connected one G203V directly to the board and it works...but not as expected. It does the same as before (just moves one way) and it seems as if it doesnt have any power. At first it moves really slowly and makes a really anoying ramping noise until its reaches the "supossed" maximum speed I got in the motors tuning options, but it doesnt even seems to be able to move a litle sheet of paper..

Thanks for help

[awerby]

more is better. Did you set the step/direction input timing as suggested in that troubleshooting chart? And as Markwind suggested, did you get the pins sorted out correctly?

Andrew Werby
ComputerSculpture.com — Home Page for Discount Hardware & Software

[Merchi]

more is better. Did you set the step/direction input timing as suggested in that troubleshooting chart? And as Markwind suggested, did you get the pins sorted out correctly?

Andrew Werby
ComputerSculpture.com — Home Page for Discount Hardware & Software

How can I get more voltage from the parallel port pins ?

As written in the last comment all of the 3 axis just recognices me in one direction. If I move the other way the mach 3 notices but not my board. So this way I cant measure the difference voltage between common/direction pins.

Thanks for support

[awerby]

there's no way to boost the voltage. But I've heard that 3.3 volts is not really enough. You might look around for another computer with a stronger parallel port, just to try it out. And since you're using Geckodrives, you might try calling them during business hours (Pacific Standard Time); they're really very good at this sort of thing...

Andrew Werby
ComputerSculpture.com — Home Page for Discount Hardware & Software

[Merchi]

there's no way to boost the voltage. But I've heard that 3.3 volts is not really enough. You might look around for another computer with a stronger parallel port, just to try it out. And since you're using Geckodrives, you might try calling them during business hours (Pacific Standard Time); they're really very good at this sort of thing...

Andrew Werby
ComputerSculpture.com — Home Page for Discount Hardware & Software

Many thanks for the tip. I will try with another computer and I will contact geckodrive support in order to try to solve this problem

Thanks again

[amishx64]

there's no way to boost the voltage. But I've heard that 3.3 volts is not really enough....

Well that's not exactly true. You could just wire up a NPN transistor and resistor to each pin and add in a 5V supply.

There are also probably logic chips that will do this too. I don't know of any though, just that they probably exist.

And you could probably do this with an op amp too.

[amishx64]

Followup:

What I was trying to describe is a logic level shifter.

A chip like the TXB0104 would be more appropriate I think.

Sorry for the 2x post.

[doorknob]

Or a parallel port buffer board such as this one from CNC4PC:

CNC4PC