G540 - 4 motor connection problem

Yeah - I might open it up and see if I can find a serial number or something for the unit, and pass that to Gecko

I think Automation tech are sending Gecko a power supply, ( the same as mine ) to see if they can figure out what the issue is, should be this week sometime, in the meantime, all I can do is hookup the 48 Volt pwr supply and check the amperage, but because it spikes so fast, I don't think it will register on the multimeter

At least I can discount the voltage as the culperate, otherwise the 3 motors or two motors connected would cause the same issue - seems to be current draw related

Quote:

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Originally Posted by JAZZCNC

They expect the person fitting the unit to be competent or experienced enough to factor in that certain amount of Back Emf will be produced. It's common knowledge even at DIY level that safety factor is required which is often advised being around 10% less than Max rated voltage.

It's dangerous and foolish to assume that any manufacturer as built in "safety" factor and then Ignore the Warning Given in the Same Manufacturers Manual.!!

It's even MORE FOOLISH to thentry an Rubbish what someone with years of experience is telling you will happen if you run at those Voltages.

Now I should tell you to get stuffed you arrogant "Aussie Bastard" but in the spirit of helping people then I'll just say. Gecko after sales service is legendary so Contact Gecko tell them you your issue and they Will replace/repair the unit for you.

Oh and the Voltage Calculation is just that.? A Calculation based on the Motors parameters and should be used has guide line for Motor Voltage and doesn't mean just because your motor specs calculates that 50V is ideal voltage you can run at this voltage on the drives.!!

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I'm sorry if I have offended you - I am just getting pissed off that I bought a package of components that don't work together, and I have tried your suggestion of a lower voltage - and it still does not work

However.
If what you say is correct, then why when I run 3 motors at 49 volts, does the system run absolutely flawlessly - no burning, no faults, no issues

Hook up a 4th motor, and fault occurs - directly proportionately to the 4 motor load I believe. Even at 42 Volts it still occurs. - that is 20% safety factor no + the manufacturers' unpublished safety factor that I didn't pluck from my aussie arse either - I gained through the wisdom of the internet


Product technical datasheet - from the manufacturer, and published all over the internet everywhere you purchase the unit from.

"Supply Voltage"

15 - 50 VDC.

That means Supply voltage 15-50VDC.... So far 42V - 50V does not work, so it probably is the current protection issue they identified in 2012

2012 ? It's 2017 now. Every body else's drivers are in the bin now and they have moved on. Do yourself a favour, try to get your money back or eBay it and get some modern drives.

Man, I tried Everything!

The unit is a Sep 2016 model, everything looks intact and tests correctly, I've tried earthing and isolating everything.

Can anyone recommend a linear power supply supplier - or are they all created equal?

Nick

When choosing the voltage of an unregulated power supply you have to take in consideration the possible voltage variations of the AC line voltage which are usually +/-10%.

For example a 32V AC toroidal transformer will give you around 44V DC at 230V but 49V DC at 253V

Quote:

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Originally Posted by dachopper

I'm sorry if I have offended you - I am just getting pissed off that I bought a package of components that don't work together, and I have tried your suggestion of a lower voltage - and it still does not work

However.
If what you say is correct, then why when I run 3 motors at 49 volts, does the system run absolutely flawlessly - no burning, no faults, no issues

Hook up a 4th motor, and fault occurs - directly proportionately to the 4 motor load I believe. Even at 42 Volts it still occurs. - that is 20% safety factor no + the manufacturers' unpublished safety factor that I didn't pluck from my aussie arse either - I gained through the wisdom of the internet


Product technical datasheet - from the manufacturer, and published all over the internet everywhere you purchase the unit from.

"Supply Voltage"

15 - 50 VDC.

That means Supply voltage 15-50VDC.... So far 42V - 50V does not work, so it probably is the current protection issue they identified in 2012

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Didn't offened but does frustrate because I wouldn't waste my time posting info trying to help if wasn't sure of what I'm saying so when someone with very little experience then try's to tell me I'm talking bo~%&oxs does slighty piss me off.

Just about every drive on the market as specified operating voltage range just like Gecko have and in theory they should work fine if voltage is within that range.
Now where the problem comes from is the fact Steppers can be and are used in wide range of applications. Lots of these applications will be slow moving or light weight applications so will produce very little inertia or back EMF. Then in which case provided regulated 50V supply is used there won't be any issue.

However for CNC router this isn't the case and inertia pushing gantry from high feeds so will create back emf and push the voltage above the 50v safe limit.! . . Ahh but where using Regulated supply your thinking so no problem. . :yahoo: . . . .Wrong now you create another problem.?
Regulated supplies will have protection built into them so if voltage/current is feed back it clamps the supply and shuts down.! . . . Not good.

So you see it's not so black and white.

Now do your self a favor contact Gecko USA not your supplier and tell them the problem and I'm sure they will help you or advise what it could be.

Or better still do your self Bigger favor and sell it then buy Leadshine AM882 Digital drives and use Unregulated toroidal supply. The difference in machine performance will be night and day and you'll never have any issues.

Quote:

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Originally Posted by JAZZCNC

Or better still do your self Bigger favor and sell it then buy Leadshine AM882 Digital drives and use Unregulated toroidal supply. The difference in machine performance will be night and day and you'll never have any issues.

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Totally agree! I've got the AM882 drives on his recommendation and I'm very satisfied by their performance. Lower noise and vibrations, better performance at high speeds, software configuration, auto-tunning, etc. And you can give your steppers 60-65V for better performance.

Quote:

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Originally Posted by paulus.v

Totally agree! I've got the AM882 drives on his recommendation and I'm very satisfied by their performance. Lower noise and vibrations, better performance at high speeds, software configuration, auto-tunning, etc. And you can give your steppers 60-65V for better performance.

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Well - I've got the G540 working on 30 volts with the 4 motors, I've just had to ramp down the voltage significantly to achieve it.

Looked at the leadshine - are you using a Bob or some other thing to break the sigs out into a useable format to run wires?

I ran the G540 for a 7 hour job, and it completed without any problems, so - apart from the fault causing me to run slower, I'm going to reserve my judgement - hopefully there is a simple fix


I'm going to call Gecko tomorrow and see if I can get anywhere with them.

Quote:

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Originally Posted by dachopper

Looked at the leadshine - are you using a Bob or some other thing to break the sigs out into a useable format to run wires?

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I'm still using the parallel port with a good BOB.

Update - I finally skyped tech support, and they have been great.

The problem appears to be the result of several factors, but is related to switching power supply / 4 motor combo / and a setting on the G540

Gecko are testing out a mod to the G540 to see if they can get it to work with this power supply in particular, and the 4 motors I have.

I'll let you know the result incase others have the same issue.

Nick