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Offline RICH

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Re: Motor Problem
« Reply #10 on: October 16, 2011, 09:40:17 AM »
WB1,
Test per what Tweakie posted. Remove the BOB, use the attached xml file. See if the motors respond, if they do then try the bob.
Make sure you that the BOB has 5V going to it.
Of course you will need to revise the motor tuning based on your system.
RICH

Offline WB1

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Re: Motor Problem
« Reply #11 on: October 17, 2011, 01:24:13 AM »
Hi, so I've measured what you guys have been saying and I'm getting approximately 0V for a Lo Signal and 3.3V for a Hi signal.

Tweakie when you say
Quote
If the max voltage you get is 3.3Volts then you may have a problem with that BoB.
I'm taking that to mean the BOB is not compatible with the computer? Because this was all working 12 months ago.

Do you guys think it could be to do with the length of the parallel port cable? When I had it set up 12 months previously the parallel port cable was only 1 metre long. The cable I'm now using would be approximately 5 metres. Is it possible voltage drop is the problem. I guess I could check the actual voltage coming out of the parallel port on the computer (its just a pain to get to :()

I'll have another look. cheers.

Online Tweakie.CNC

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Re: Motor Problem
« Reply #12 on: October 17, 2011, 01:46:07 AM »
WB1,

The extra length of cable may just have been the last straw.
Best solution would seem that you need a BoB witch specifically accepts the 3.3V input. There are some to choose from here  http://www.cnc4pc.com/Store/osc/index.php?cPath=33&osCsid=671377cb99e791846d6b802f889e5e81

Tweakie.
Success consists of going from failure to failure without loss of enthusiasm.  Winston Churchill.

Offline WB1

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Re: Motor Problem
« Reply #13 on: October 17, 2011, 02:21:57 AM »
Yeah the last straw that was what I was thinking. The voltage coming out of the back of the computer parallel port is 3.375V the exact same as whats coming out of the parallel port cable. But of course voltage drop only occurs when you have current flowing so I can't really compare the two.

I'll try a couple more things next but I have some questions.

So is 5V or 3.3V the standard for Hi signals on the parallel port?
So a geckodrive G540 doesn't work with 3.3V?

Offline WB1

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Re: Motor Problem
« Reply #14 on: October 17, 2011, 02:58:24 AM »
Just tried moving my computer closer to the BOB and used the shorter parallel cable with RICH's xml. file. Nothing new; motor is locked stiff no movement. I've tried jogging in the motor tuning window and I've tried jogging by pressing 'tab' and using the jogging window.

I'm running out of ideas damn it! ???

Offline RICH

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Re: Motor Problem
« Reply #15 on: October 17, 2011, 06:17:04 AM »
Quote
So a geckodrive G540 doesn't work with 3.3V?
It's made to work with both voltages.

Quote
So is 5V or 3.3V the standard for Hi signals on the parallel port?
A lot of the new computers are 3.3 volts, some are dual voltage, can buy dual voltage cards , usualy there is a switch or jumper on the card
to set the output volatge. Have a look in the Mach3 Manual about Logic signals .

PC cords are usualy limited in length and you will / may have problems if they are long. Even in industry wiring signal length is limited at higher voltages
but amplifiers are used when needed but not deisrable.

Did you try the motors with the BOB removed? Is the reset button flashing?

RICH

Offline WB1

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Re: Motor Problem
« Reply #16 on: October 17, 2011, 06:50:06 AM »
Thanks for that info.

You say that some parallel port cards you can change the output voltage? I guess thats not possible if the port is built into the motherboard?

Not sure about what you mean by:
Quote
Did you try the motors with the BOB removed?

The motors won't move if the BOB isn't plugged in ??? I think I'm missing what your saying....

Online Tweakie.CNC

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Re: Motor Problem
« Reply #17 on: October 17, 2011, 07:13:25 AM »
WB1,

If it is a voltage issue, which I suspect it is then .......
The Geckos will work OK at 3.3V it's the input side of your BoB that is having the trouble. Replace the BoB with one that accepts 3.3V input signals.

Tweakie.
Success consists of going from failure to failure without loss of enthusiasm.  Winston Churchill.

Offline WB1

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Re: Motor Problem
« Reply #18 on: October 17, 2011, 07:17:30 AM »
Yes this is what I will most probably do. Everyone seems happy with their Gecko drives!

Thanks for your help!

Offline WB1

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Re: Motor Problem
« Reply #19 on: November 13, 2011, 07:41:06 PM »
Hi to anyone that was following this thread. To conclude, I bought a G540 Geckodrive from Ebay for approximately $270 AUD delivered. Besides it taking almost three weeks to arrive, (USPS seem pretty useless!) the G540 has worked like a charm. I followed the setup guide on the Gecko website. I wish I had bought this drive in the first place.

One thing I have noticed is my motors get quite warm/hot. I believe this is because of my 24VDC power supply. But a short term solution I have found is to keep your e-stop tripped. Firstly its safer. And secondly, although your motors aren't moving they have 'holding torque' which essentially means the motors are still 'working' and will heat up if left. If you just hit the e-stop you will hear the motors stop their high pitched noise. Thirdly, if your mill is in the garage, don't use it when the weather is really hot.