[the_great_snag]

Very bummed. I bought a power supply off Ebay to attempt to upgrade the power of my milling machine's stepper motors. The first one I got gave me smoke and sparks shortly after I connected it to my expensive motor driver board, then quit working.

So... I notified the seller, he immediately sent me a replacement via priority mail. I did not even have to return the fried unit. While I was waiting I also had to send my driver box back to Geckodrive Motor Controls to get repaired.

Well, anyway, today the replacement power supply arrived in the mail. The box was torn, the unit was dented, and parts rattled inside it. Naturally it did nothing when I hooked it up. I opened it up and a pressure point lever thing was knocked loose and there were some broken solder joints.

At what point does the seller have the right to quit replacing the dumb things? I wonder if it was insured? It was sent at the $5.75 flat rate Priority Mail. Does that include insurance? Anyway... long day and a crummy way to end it.

[mactec54]

What was the brand name of the power supply, & how did you wire it

[the_great_snag]

Genssi?

Green to ground, White to "N" and Black to "L".

The first one powered up, but it killed my Gecko before it committed suicide. My Gecko would work on my other 24V power supply, but two of the driver boards were toasted. The Gecko would not do its self-checks (no "Fault" light on startup) on the 48V unit either. I figure one is a lemon, but two bad units?

Anyway, I always follow factory wiring diagrams when I set up a machine. I had the correct current set resistors installed and everything.

[mactec54]

the_great_snag

It's very difficult to wire the input power incorrect, But if you had the 48V switched + / - when you wired to the Gecko this is what can cause the magic smoke to happen, Did you check the output voltage ( 48v ) before you connected it to the Drives, if this was correct, then you most likely, reversed the + / - when you connected it to the Gecko, by the damage caused to the Gecko, the repair team will know what happened to the input power, as to whether it was wired correct or not

Did you have the power selector switch set to 115v or 220v , this would not of caused the problem, but the power supply would not of worked correctly

It seems the second power supply was damaged in shipping, In the post I asked what power supply Brand name, some of these power supplies are not made as well as others, it is good for others to read what power supply you used/ got, so they don't make the same mistake, if it was the power supply at fault

Mean Well are one of the best power supplies to get

[the_great_snag]

Yes, It would be rather hard to mess up the A/C side wiring. lol Especially since the wires in my power cable are color coded. I also only connected the Gecko with the power off and I double-checked the polarity of hte voltage outputs, as well as how much voltage I was getting. The Gecko never gave me magic smoke. It was the power supply. The Gecko simply would not work on 2 axes and did not run the self-check (fault light) thing when powered up.

Also, all my motors were wired correctly, as they all worked fine on the axes that worked. I am pretty sure the Gecko had 2 bad G250x boards either before or after I hooked it up. I bought it off Ebay as New, but who knows? I just found it strange that the Gecko worked more stably with my old 24V power supply I had for my old BoB and driver setup.

I always slide the selector back and forth when I get a new PS do ensure the "115" is visible and that it's slid all the way to that position.

I suspect it got crushed or dropped in transit. It was in a simple cardboard box, but that was only in a flat rate envelope. No other padding. I cracked it open to see if anything obvious was wrong after it would not run, and there was a small metal lever holding a device to the side of the housing that had been jarred loose in transit. I know how it was supposed to be oriented because I cracked open my other one when it died. I also found a broken solder joint, but fixing it did nothing.

Also the large housing with the copper windings (transformer?) showed signs of melting in the clear coating that covers it. Anyway, I was not able to find any voltage downstream from there. In the previous dead power supply I was able to find voltage most places except near the outputs, naturally. Anyway, as you may have guessed, I am not an electronics tech, and I am a bit scared of power supplies, but curiosity overruled my common sense.

I was checking out Mean Well supplies last night. I think that is the course I will take.

[Al_The_Man]

I stay away from SMPS if possible, they are not required for steppers/servo's anyway.
The linear supply is heavier and slightly more $$ but are much more rugged and and easy to fix, in the rare eventuality that they fail.
Also easy to build DIY.
Al.

[the_great_snag]

PS. the Ebay seller was extremely helpful and responsive. I do not wish to impugn his good name by sharing it here.

[the_great_snag]

Al, what is an SMPS?

I would be interested in making a linear PS. Any good articles on how to build them. I know Probotix sells some components for making them.

[the_great_snag]

How about this one? Mean Well 480W Power Supply 48V DC Switching Regulator PFC DRP 480s 48 | eBay

One dumb question, The diagrams seem to indicated that you ground your DC power to the -V terminals. Is that correct?

[Al_The_Man]

SMPS = Switch Mode Power Supplies.
If you Google Linear power supply I am sure you will have 100's to pick from there is basically only three components, Transformer, Bridge, Capacitor.
I usually source Toroidal transformers as they are also easy to put a small few turns overwind on if needed for a auxilliary LV supply.
There is a guy builds Toridals transf. and also the complete P.S. AKA Antec he also lists on ebay as Jonango.
Al.

[Al_The_Man]

One dumb question, The diagrams seem to indicated that you ground your DC power to the -V terminals. Is that correct?

You can if you wish, as long as on a linear supply there are no earth ground connections on the transformer connections itself however.
Al.

[mactec54]

One dumb question, The diagrams seem to indicated that you ground your DC power to the -V terminals. Is that correct?

No it is not a dumb question, a very good question

When you wire these to your AC input power you have your ground wire, this is Grounding the Chassis of the Power Supply, so if you were to ground the 48V DC output, you would have a Ground loop which you don't want to have, it is a bad idea to Ground the DC negative to Earth Ground in this case

[mactec54]

PS. the Ebay seller was extremely helpful and responsive. I do not wish to impugn his good name by sharing it here.

The Brand Name of the Power Supply has nothing to do with the Ebay seller

[Al_The_Man]

Earth grounding the DC supply commons is done all the time, it is usually a question of what method you subscribe to, incidentally this is done on you PC P.S. where the common is taken to earth ground automatically.
Many do not really understand what a ground loop really is, as long as all points are equi-potential bonded no 'ground loop' exists.
http://www.automation.siemens.com/do.../emv_r.pdf?p=1
Al.

[mactec54]

Earth grounding the DC supply commons is done all the time, it is usually a question of what method you subscribe to, incidentally this is done on you PC P.S. where the common is taken to earth ground automatically.
Many do not really understand what a ground loop really is, as long as all points are equi-potential bonded no 'ground loop' exists.
http://www.automation.siemens.com/do.../emv_r.pdf?p=1 .

Yes Equipotential Bonding, if the person knows what they are doing, theirs no point in telling hobby users/ builders this, if they get it wrong which most will, they will damage their low voltage electronics

As I said above if he wired the 48v dc Negative to Earth Ground , he would have a Ground Loop as the Switching Power Supply is already Grounded to Earth Ground

I just tested 4 different PC power supplies, & none of them have the DC common connected to Ground Earth & these a large wattage PC power Supplies

[Al_The_Man]

Yes switching supplies in particular come isolated from earth ground, this gives the option of earth grounding the common if you subscribe to this method, some insist on total isolation between systems and the other method which I have always subscribed to is making all supply commons, common to earth ground.
It is similar to those that attempt to galvanically isolate their AC spindle say, from their PC by using opto isolators, it does allow transition from low voltage DC to 120/240v AC, but does not galvanically isolate, the PC P.S. common is earth grounded and so is the AC spindle via the grounded neutral.
Hence no Galvanic isolation.
Al.