Can a G540 take 105 volts!

[bret4]

I just put my cnc electronics together. I first tested my power supply and it was working perfectly. It put out 48 volts right out of the box. After putting everything together I couldn't get the motors to run. The drive would go to fault whenever I tried to run a motor.

After a lot of playing with mach3 trying to get my G540 to run my motors I started to recheck everything. All wiring is right. What could it be? Turns out my new power supply is now putting out 105 volts. It is adjustable and would only adjust down to 85 volts. So now I know the power supply went bad as soon as I started using it.

The big question is can the G540 take that kind of over voltage?

[john_100]

as the maximum supply voltage for the G540 is 50V

it looks like you will need to send it back to Geckodrive inc for repair
but give them a call , if you are realy lucky you may have just blown the internal fuse


give the power supply supplier a call for a replacement and see if they will pay for the repair or replacement of the stepper drivers
no harm in asking

John

[bret4]

I know the max voltage is 50 volts but I wonder if there is any over voltage protection?

I wouldn't send the g540 back to gecko. The people that sold me the bad power supply also sold me the g540. I would have them send me a new one and take back the old one. After all it is their fault for selling defective power supplies.

[john_100]

Hi Bret,

I've not been able to find any info on the level of over load the G540 survives
even when it blows the internal fuse
but over twice the normal supply voltage is asking a lot from any protection circuit

[tumutbound]

I seem to recall that an absolute maximum that can be applied to the G540 is 64V.
Not in any way recommended or supported, just a value beyond which things are guaranteed to fail.

[bret4]

Did some checking on the Gecko site and they say 50 volts max or it can be damaged.

[Al_The_Man]

Buy a linear supply, more durable, safer (on equipment).
Al.

[bret4]

I was going to get a keling KL-4813 unregulated supply for my next one. Been through two of these regulated ones and they keep turning out to be junk. Just to many things to go wrong with the regulated ones. Won't be buying a regulated one again.

Must be why your Al the man.

[bret4]

OK here is an update. I checked the power supply again and for some reason I can get it to put out 48 volts again. I figured if the gecko g540 is blown what is the harm in giving it another test. Here is what I did.

I plugged one motor into the G540 and tried to get it to run with mach3. For my machine I figure I should be able to get 150 inches a minute from it. I can't get it to go faster than 30 inches a minute without the power supply kicking out. It cycles on and off until I reset the E-Stop switch. Then I comes back on and the motor holds fine.

The next thing I did was add a second motor. With two motors attached I can't get the the speed of just one motor up to 5 inches a minute before it does the same thing.

The last thing I did was attach all three motors. With all three motors attached the power supply will not even let them just sit there at their holding point. As soon as I turn on the power the power supply cycles on and off over and over again. I put a volt meter on the power supply at this point and you can see the voltage cycle up and down from around 40 something volts down to almost nothing.

More load makes the problem worst. If that doesn't sound like a power supply problem then I don't know what it is. At least it seems like the G540 is still good. Maybe the high voltage I had before was having my digital meter on the wrong setting or it was at such a low current that it did no harm. The G540 seems to work fine at low power draw with one motor. I would think it would just not work at all if it took so much over voltage. Could be lucky there.

[__Britt]

Yeah, sounds like a dead power supply. I suspect the switching regulator is at fault; and that you only get 105 volts out when there is no load on the unit... so you may not have exposed the gecko to the high voltage after all (well, one hopes!).

So - yes, I would suggest getting a transformer-type unregulated power supply for your machine; and avoiding the switcher-types in the future.

[bret4]

That's exactly what I am going to do. For now on I'll stay with the unregulated power supplies. Not much difference in price and less to go wrong. A lesson learned.