I purchased my QNAP TS-653D 8GB mem on 16th Dec 2020.
After 5.5 years the factory power supply became unreliable. It provides 12V under 0 load, but when I use it with my NAS it is no longer able to provide stable 12V and my HDDs keeps spinning-up, restarting and the NAS is no longer able to boot.
And 6 weeks before this I also had strange shutdown. But after that I was able to start the NAS with the old power-supply.
This is a NAS with max 6 3.5" HDDs. As of now fully loaded.
Additional to this external fan is plugged in one USB and another external raid enclosure (with own power supply) to another USB. 2 Cat5e cables also plugged in with link aggregation for 2.5Gbps.
To resolve the situation I purchased one brand new Meanwell GST220A12-R7B.
This has max output 180W / 15A on 12V (the factory power supply was 120W only!)
It took 3 days and the new power supply arrived from Germany.
I plugged in - and NAS is not starting.
I compared the old and new power supply, both are 4-pin mini DIN plugs but the pin layout was different!
The factory plug has 12V on pin 3 and 4. While the new Menawell has 12V on pins 2 and 4.
I cut the branch new Meanwell - 4 wires, one of the GND was also attached to the outer sleve → I could not rewire. That would have put 12V on the outer sleve.
So I cut the old power supply as well. Just 1 wire + GND is around as second also as shield → cross connected old output cable and new power supply with 2x3 WAGO 221, sealed and tested again.
NAS works again, stable.
After 12h of RAID6 resync all is OK now.
Engineers: It would be great if factory powers supply were reliable, and sized for max load. Also shipped with standardized output plug (4pin DIN is not standard!).
External power supplies are used in a lot of equipment as they are cheap and save space in the device. But they are very unreliable (see “cheap”). I despise external supplies.
QNAP buys these from likely multiple low cost Chinese outfits and so their engineers have nothing to do with it.
When replacing a power supply, always, always, always make sure you understand the pin-outs before connecting. As @dolbyman said, you are very lucky you didn’t let the smoke out of your NAS!
Fortunately, external supplies are quite easy to replace and readily available…
I just asked AI first if these 4-pin power-supples are standard. I got a “yes” that time:)
Later when I realized that they are not, the AI immediately told that “sure, those are not standard”…
Best to ask AI twice:)
So I guess I was just lucky or either the Meanwell or the NAS has protection agains such misconfiguration. Meanwell has this “Hiccup Mode” protection so probably that saved me.
Yes I understand that power supply is not manufactured by QNAP. But they can chose the power (180W instead of 120W) and also they can select the output plug (something standard over this non-standard one).
What is to say that QNAP’s configuration is not standard? Who’s to say that you didn’t buy a standard one?
Also, you say in your original post that GND was attached to the outer sleeve of the Meanwell and that would have put 12V on the outer sleeve. No it wouldn’t have. GND = 0V. As the outer sleeve of DIN connectors is typically connected to the chassis, I highly doubt any supply would put 12V on the outer sleeve. I’ve seen coaxial power connectors with the + voltage on the outer conductor but never in a DIN configuration.
Also, the size of the power supply is a driver of its cost. Your NAS typically draws 35 Watts fully loaded. Let’s say it peaks at 75 W. A 120W supply is more than enough. A 180W supply does nothing to improve the situation and is more cost and larger size and quite possible less efficiency.
What I meant here: it was not possible to rewire the Meanwell to provide 12V on pin 3,4 (as expected by the NAS) because pin3 was originally GND and that was also attached to outer sleeve (GND). That’s why I had to use the old output plug instead.
as mentioned drive has 6 HDDs + external fan on USB + NAS CPU + 2 internal fans
I was calculating with the power-on max load (assuming this NAS does not support staggered spin-up). This exceeds 120W.
I agree that normal load is fraction of this.
This does not calculate with inrush current of all drives, fans, cpu, etc.
Yes this power supply is a bit larger, has same (or somewhat less) price as a new QNAP 120W factory power supply.
According to Meanwell data sheets it has high efficiency on average load (20%). So extra power consumption is negligible.
What I expect is that a 180W PSU will last much longer due to lower operating temperatures, which extends the lifespan of the electrolytic capacitors (which was likely the issue with the old PSU).
I really don’t think that the inrush current is going to be any kind of an issue with a 120W vs. a 180W supply. The supply by nature of its design may limit the inrush current anyhow.
I doubt the difference in the power rating of the supplies is going to add to the improvement in lifetime. What will make a difference is the quality of the supply. Meanwell makes a very good product and I think you will be happy with it. Not sure who the manufacturer was of the old supply but it was likely made by the lowest priced bidder! You are right - it may be the electrolytic but then given that the supply output 12V with no load but couldn’t supply voltage under load, it may also be a failure in the controller IC for the power supply. But who knows.
Anyhow, you should be good with your new supply. Glad you got things working!
