MeanWell power supply quality control issues!

[mos6502]

You can't say that the CapXons are bad in this PSU unless you have the schematic.

The life expectancy of an electrolytic cap is primarily a function of the ripple current that it has to take.

If the CapXons aren't subjected to heavy ripple currents, but the Nippon Chemi-Cons are, it's very well possible that the Nippon Chemi-Cons will die before the CapXons.

[free_electron]

You can't say that the CapXons are bad in this PSU unless you have the schematic.

The life expectancy of an electrolytic cap is primarily a function of the ripple current that it has to take.

If the CapXons aren't subjected to heavy ripple currents, but the Nippon Chemi-Cons are, it's very well possible that the Nippon Chemi-Cons will die before the CapXons.

Exactly.
People are too eager to shot capacitors in power supplies.

And the coment about ther eonly beeing so many space between bus bar and cover... don;t press on the damn cover. i'm sure the datasheet will tell you how much warp there is allowed to be.
For the same reasons that harddisk covers have big warning stickers saying : dont drop , don't press here.

I don't see a single thing wrong with that power supply.

[metalphreak]

CapXon got a really bad name in the industry for a relatively short period of time where they were just making utter garbage. Now they're probably just as good (as bad?) as all the other non-Tier-1 suppliers.

The fact they aren't using CapXon all round for everything kind of indicates they've only specced them for non-critical parts of the design.

The busbar clearance issue seems odd. Maybe they did somehow forget an insulating sheet on yours. Is the outer casing quite rigid/thick aluminium? If it's within the clearances required for that level of DC voltage, and it's a fairly solid casing, it shouldn't be an issue. A supply like that isn't meant to be used in an environment where it gets bashed around.

If you hadn't opened it, would you have ever known if it continued to work fine? Just because it looks poorly designed doesn't mean it is. Mean Well make good quality products, but they are never marketed as laboratory grade super premium top end supplies or anything.


If you want to see poor QA, check out my thread where I discovered why my chinese no-name supply started smoking. They put in a much smaller value resistor for the output load than what it should have been, putting the poor 5W resistor past it's rating.

[free_electron]

what people dont realise is that capxon is one of the largest manufacturers of electrode material....
Many a capacitor manufacturer doesnt make that themselves ! So your rubycons may very well have capxon electrode laminates in them ....

this whole bad capacitor things stems from 2 misconceptions

1) in the early 2000's there was a stolen chemical formula for a dielectric . Mitsubishi chemicals had  an ew electrolyte yielding a much higher capacitance density. this formula was stolen by some Chinese outfit. only they did not realize they had an incomplete formula. a key ingredient stabilizing the electrolyte long-term and over temperature was missing... the Chinese outfit sold the electrolyte to many capacitor manufacturers and they sold oodles because it was cheaper than MCM electrolyte. The electrolyte hit the fan when it turned out that after a few months to a year under heave load the electrolyte started disintegrating , giving off hydrogen gas giving burst capacitors...

2) many capacitors are wrongly applied. inexperienced designers and beancounter malpractices pick the cheapest possible part. and that may , form a technical perspective, be the wrong part. Pulse loading , esr , and other parameters are overlooked yielding prematurely dying capacitors.
especially switch mode power supply tank capacitors live a VERY hard life and are subject to pulse current with high crest factors. combine dielectric losses with esr losses and you are boiling off the capacitor over time.

1) has been solved a long time ago.

2) will only get worse. Consumer stuff has, profit wise, hit rock bottom so the beancounters are pulling harder and harder and the quality of the design 'engineers' that rolls out of the education institutes is getting weaker and weaker when it comes to understanding components. They may be very good at coding and theoretical stuff but have no understanding of part fundamentals. Having to listen to 10 lectures on capacitors and 10 on resistors is boring.... besides, the old farts that knew that stuff have long since retired and been replaced by young whippersnappers that want to teach the theoretical stuff..

[Kjelt]

1) this formula was stolen by some Chinese outfit. only they did not realize they had an incomplete formula. a key ingredient stabilizing the electrolyte long-term and over temperature was missing... the Chinese outfit sold the electrolyte to many capacitor manufacturers and they sold oodles because it was cheaper than MCM electrolyte. The electrolyte hit the fan when it turned out that after a few months to a year under heave load the electrolyte started disintegrating , giving off hydrogen gas giving burst capacitors...

If a company really has any form of QA in their ranks they should test a new (part of) product before putting it in their own product.
So this says more about the companies that did this namely that they can not guarantee ANY of their products and it could happen just as easily tomorrow due some other production failure or cheap/fake supplier. So the big question is if your company would trust such a company?
Then there is this shortage of electrolytic products due to the disaster in Japan a few years ago and products couldn't be made due to the fact that the parts were not in stock. A lot of companies then switched to other brands, and this was not always a succes (and then I put it very mildly).

[electronac]

Hello;
Seeing that you get several photos of the Power Supply RSP-1500-24, by chance you have pictures of the resistors R25 and R90?
by a short circuit has been burned and I can not identify their values.
Thank you.

[AmmoJammo]

Old thread (I didn't dig this one up!) but it looks like there's a plastic insulation sheet inside the lid anyway

[AlanR]

Hello;
Seeing that you get several photos of the Power Supply RSP-1500-24, by chance you have pictures of the resistors R25 and R90?
by a short circuit has been burned and I can not identify their values.
Thank you.

I am not going to help you. I am not trying to be mean, but the power supply is embedded into a test rack as a power source for 1/4 to 3/4 horsepower 24 volt DC motor characterization testing and motor speed controller design testing, and I am not going to through all the hassle of having to disconnect everything and then having to open the power supply up for two resistors you need to look at. Just contact Meanwell for the values or ask someone else that does not have their power supply inside a test rack setup.

[LabSpokane]

If the power supply is for play/fun - maybe it's worth your time fixing it.  If this power supply actually needs to be dependable, just scrap the Meanwell and get a decent power supply.  We banned Meanwell power supplies in a previous life after we had nearly a 100% failure rate with *dozens* of Meanwell power supplies.  These were all ordered through legit distribution channels, so I believe they were "genuine."

After the tens of thousands in warranty costs, Meanwells were not cheaper than a quality power supply. 

[electronac]

Alan R: well thanks for responding me. I agree with you, neither do i would disarm it for to take 2 photos.
The idea was to see if between the photos you already  took when you had disarm the power supply, it was  the resistance I need.
i already contacted with MeanWell , I was told that I contact the local representative.
It does not work, the place has no idea because they do not open the power supplies, they only buy and sell.
Anyway, thank you.
I hope you understand, because my English is not very good.