What power can the SATA hat support, Losing disks


Starting this as a fresh topic as I want a proper answer.

I am running 4 X 2Tb WD blue drives, and have done a fair bit of testing on this.

  1. if i install a single drive it runs with out issue for days in any of the 4 slots

  2. if i install 2 drives the same

  3. If i install 3 drives again works fine and is stable, and again i can move the drives around and they work in any combination of slots

  4. if i install all 4 drives then 2 things happen
    a. Not all drives come up at boot
    b. All drives come up but over the next 24/48 hours i will lose one (light turns of no longer accessable)

The slot that the drive fails in and the drive its self is not consistent. Ie. i might boot it once and drive 2 in slot 2 fails to come up, then reboot and it will be drive 3 in slot 3. Then i will switch all dvices about and it will be drive 4 in slot 1…

Go back to only 3 drives installed and its back to being stable.

The only thing i can think of is the power draw goes to high or is not stable and the drive crashes. I am assuming that on boot all drives spin up togather and there is no squence to them powering on?

Using the power supply that came with the SATA hat so that should be ample llooking at the specs of the drives from WD.

So my question is what power can the HAT handle how can i figure out if this is a power issue, the dmsg log shows nothing, the drive simple does not appear.

People have said clean this or check that, but as above the issues is not following slots or drives so its not dirty connecters or issues with drives. In my past 20+ years working in IT this jsut seems like a power issue but i cant find any were the specs on the powermangemnt in the HAT?

I think you did not mention, how do you power the whole devices.

The power option is mentioned here:



No i did, as i stated i power it with the power supply it came with it when you get the metel case and powers it though the 12V jack. (the power supply it comes with is 5amp)

4 X 2Tb WD blue drives

Are they 2.5 inch or 3.5 inch?

2.5inch. The metal case only fits 2.5inch drives

Can you photo front part of your hdd? Or say which model it is.

its the WD20SPZX, - Western Digital 2 TB SATA 2.5 Hard Drive - Blue

Based on WD datasheet

It’s 1A, so it’s 4A current in total, since it’s raspi hat and not RockPi I’m unsure regarding how it’s powered, but in case of penta hat I had a problem with similar power consumption on spin-up (i.e. one of 5 drives could require more power than it’s actually said in datasheet when it’s starts up).
After i switched to ssd even through they require more ampers (1.1A) there were no problems with them

Yes I know the power draw of the drives, but that not the question I am asking. I want to know what the specs of the power supply regulator of the HAT are.

Really though as its sold as a 4 drive NAS then really it shold be able to support 4 HDD espical when said drives are one one of the most common make and size for a NAS. I dont think “swap out 4 perfectly good drives for 4 new drives” is a acceptable solution

Why would you run SSD’d when the harddware limits of the HAT mean its not even capable of reaching the though put of a single SSD drive, and the limit of the pi 1Gbs network is would limit though put to a single drive thoughput seppd. Buy a £50 SATA board and plug in £600+ worth of SSD to lose 75% of the possible preformance? It cant meet the throughput the 4 spinning HHD can produce, let alone SSD’s.

But back to my origianl question I still want to know the specs of the power supply and power regulation of the HAT. I am not keen to waste more money on this product, nor do i want to destroy it by powering it with a supply and having it burn out. (i doubt very much it has any over charge protection).

I know this is a cheap cheap NAS solution i get that I purchased it as a “toy” to play with to use spare drives i have laying around. And never expected it to compare with other more establised solutions (it runs on a PI and USB 3 with no hardware storage acceleration) but i think its resonable to expect it to support 4 standard drives when it sold as a 4 drive adaptor.

Wow, yours ssd is mich more costly than what i have spent on mine.

And what i said about ssd is just my example, since i anyway will update to rk3588, which will allow me to go to 10gbe. So i didn’t see any reasons not to buy them now.

As for exact specs, yes, only devs may help you or someone who does know which power controller is used in hat. And may you test insert 3hdd then insert one more, after initial spinup (of first 3) finish

P.S.At least I’m happy, that you do understand, that it’s sata over usb with arm64, which is…not great.

For my day job I work with enterprise storage and virtulisation like netapp, purestorage, vmware and nutanix.

What SSD do you have? the average cost of a 2Tbyts main stream drive is ~£150 so 4 of these is around £600?

But yes the Pi is limited when it comes to storage, its fine as a backup / simple media streaming device but it is deffetnly always going to be the bottle neck here. :slight_smile:

Cheers for the comments by the way, always greatful when people take time to reply.

Don’t see how is experience from enterprise level may be applied here. Not even talking about vmware and nutanix, they have nothing to do with power supply for hdd. Synology as closer to what we have there, rather than netapp

As for ssd cost - i guess i miscalculated how much £ cost right now in my local value. Sorry. Then regarding cost it’s correct. As for my ssd - it’s 870 evo 1tb (around 120$ per one right now)