Gert
Posts: 147
Joined: Wed Oct 24, 2012 10:19 pm

More disks on RPI4B -> Powered HUB or bigger supply ?

Tue Sep 17, 2019 12:18 am

Hello All,

Follow-up on the thread : https://www.raspberrypi.org/forums/view ... 6&t=251437

The Seagate 5T disk powers up and works fine on the RPI4B with the 3A AC adapter (Came as part of the 'Vilros' Kit from Amazon).

Now the stretch-goal was to have both the 2T and the 5T disk attached at the same time. That would be very helpful to copy the almost 2T data over to the new disk.

However running the two disks failed. The syslog truthfully said that the drive(s) reported a current violation.

Now what?
  • Get a powered hub (although the list gets short when you want one with >3A power supply)
  • Simply attach a beefier 5V supply directly to the RIP4B USB-C power port.
I like the second idea. What do you think?

Lets say I get a 5A supply (these are usually sold as Mac chargers)
  • Would that work?
  • It was stated in the prev. thread that the 5V USB signal is connected in parallel so a beefier supply would do it.
Your ideas are welcome.

Cheers,
Gert

PS : Follow-up Q : Anybody have recommendations for a ~25W-30W AC adapter that has been tested with RPI ?
Last edited by Gert on Tue Sep 17, 2019 12:31 am, edited 2 times in total.

klricks
Posts: 6609
Joined: Sat Jan 12, 2013 3:01 am
Location: Grants Pass, OR, USA
Contact: Website

Re: More disks on RPI4B -> Powered HUB or bigger supply ?

Tue Sep 17, 2019 12:27 am

The 5V USB power (combined total), is limited to 1.2A by the USB controller chip. That is usually enough to run 1 HDD only.
Providing more Amps to the RPi power input will not help.
Last edited by klricks on Tue Sep 17, 2019 12:34 am, edited 1 time in total.
Unless specified otherwise my response is based on the latest and fully updated Raspbian Buster w/ Desktop OS.

Gert
Posts: 147
Joined: Wed Oct 24, 2012 10:19 pm

Re: More disks on RPI4B -> Powered HUB or bigger supply ?

Tue Sep 17, 2019 12:33 am

Hi,
klricks wrote:
Tue Sep 17, 2019 12:27 am
The 5V USB power is limited to 1.2A by the USB controller chip. That is usually enough to run 1 HDD only.
Providing more Amps to the RPi power input will not help.
In prev. thread rpdom said : "Unless things have changed on the Pi4, all the power pins for the USB ports are connected together. That means you can take the full 1.2A from a single port."

And what about feeding the power into the GPIO 5V terminal? No USB3 power controller there?

Cheers,
Gert

klricks
Posts: 6609
Joined: Sat Jan 12, 2013 3:01 am
Location: Grants Pass, OR, USA
Contact: Website

Re: More disks on RPI4B -> Powered HUB or bigger supply ?

Tue Sep 17, 2019 12:43 am

Gert wrote:
Tue Sep 17, 2019 12:33 am
Hi,
klricks wrote:
Tue Sep 17, 2019 12:27 am
The 5V USB power is limited to 1.2A by the USB controller chip. That is usually enough to run 1 HDD only.
Providing more Amps to the RPi power input will not help.
In prev. thread rpdom said : "Unless things have changed on the Pi4, all the power pins for the USB ports are connected together. That means you can take the full 1.2A from a single port."

And what about feeding the power into the GPIO 5V terminal? No USB3 power controller there?

Cheers,
Gert
True the 4 ports are connected together..... But the combined total still cannot exceed 1.2A.
Feeding 5V to the power connector or GPIO is the same connection and will still go through the USB power control circuitry.
Unless specified otherwise my response is based on the latest and fully updated Raspbian Buster w/ Desktop OS.

LTolledo
Posts: 2000
Joined: Sat Mar 17, 2018 7:29 am
Location: Anime Heartland

Re: More disks on RPI4B -> Powered HUB or bigger supply ?

Wed Sep 18, 2019 9:45 am

power the external HDDs separately so that means using a powered hub

but alas! there are some powered hub that dont work well with the RPi4B... so you'd better do some intensive research before acquiring one...

another (messy) option is to hack the sata to usb 3.0 adapter to get its power from another source (not getting its power from the USB port)


for my recently completed NAS project (picture posted somewhere in this forum), am using 2 x 8TB 3.5" HDDs.
..found the link..
https://www.raspberrypi.org/forums/view ... 7#p1536207
"Don't come to me with 'issues' for I don't know how to deal with those
Come to me with 'problems' and I'll help you find solutions"

Some people be like:
"Help me! Am drowning! But dont you dare touch me nor come near me!"

castletonroad
Posts: 97
Joined: Sat Jul 25, 2015 11:23 pm

Re: More disks on RPI4B -> Powered HUB or bigger supply ?

Wed Sep 18, 2019 9:55 pm

I use a powered USB hub (actually, a Toshiba U3 Dynadock) to connect two 1TB USB drives to my pi4 for my nextcloud server.
Raspberry Pi 4 Model B | Raspberry Pi 3 Model B | Raspberry Pi 2 Model B

Return to “Networking and servers”