Hello,
I would like to setup a small VIM3 cluster ( 3 to 5 vim3) but i would like to avoid to have a power supply for each board.
Do you know some powerfull power supplies that can work for this kind of setup ? (for example a big usb-c charger ?? ) . For example, picocluster has built a power supply for RPI4 cluster (see https://www.picocluster.com/blogs/picocluster-assembly-instructions/assemble-pico-5h-rpi4 )
Regards,
yes it is quite possible, your example fits!
any that fits the characteristics of vim, you will have to do the wiring yourself, I think 4-5A will be fine, but depending on the task
@pea13 well, it is dependent on the Task, since I see most clusters not connected to any peripherals, and are just doing computational tasks, we can prevent power deprivation give 10w minimum to each board…
so if you wanted 5 boards, you would need up to 50w,
you can use a wall powered USB Hub, like this one,
You can Take inspiration from @Birty’s Miner project, he has multiple VIM3’s attached to a backplate, providing data and power…
Please review all your possible choices…
If you’re interested in a cluster then I can get you one of my backplane boards to test if you want. Happy to make you one and let you have it for the cost of postage - be interested to get someone else using one! It provides power and networking via the usb connection on the vim3 boards - so only one power supply needed - can do up to 3A per port. All I would ask is you feed back any issues and share results here.
Can also do you a good deal on (new) vim3 boards if you want to buy them at the same time!
This is becoming more like a back alley deal, 
you bought them surplus by chance ?
Also worth noting that the usb hubs won’t provide enough power per port to reliably run a load of vim3 board (at least in the ones I tested) which is why I ended up going down the route I did
Bought a load from khadas when they came out and have been too busy with work to use them all so far!
must be nice to have a be a local/international distributor, I wish I could be one in my locality, could really shake up all the RPi users…
yes, you are very familiar with this topic
is it some kind of voltage distributor, can you show a picture if possible?
see here…
thanks, if i’m not wrong, this is a test bench for checking Khadas boards, good solution
No this is a powered backplane for running multiple vim3 boards in a cluster. Each vim3 connects via a usb c plug on the board and each plug provide 5v at up to 3A. There is one controller port and 4 downstream ports based on a usb hub chip and power control chips. These provide individual power control to the ports (for hard reset) and also current limit in case of shorts etc. The same usb c socket on the vim 3 is used to provide ethernet over usb.
This means you need one power supply (I’m using am LRS-100-5) this backplane and vim3 board to set up a cluster.
Board also has a step up converter to power 12v fans for cooling the cluster and ability to measure current for both mains input and each of the 4 downstream vim3 boards.
All the info from the backplane is interfaced with the vim3 used as a controller over an I2C interface (the 3 wires over the boards in the picture above).
Have also brought all this info out onto a web interface that also runs on the controller board
What is the manager of the operation ?
thanks for the details!
There’s a couple of small microcontrollers on the backplane to handle the I2C Comms and then one of the VIM3 boards does the rest. But not need to do any control - out of the box it works as a 5 port usb hub with 3A port current limited at 3.2A per port
It is a very cool design, never have I ever seen a MCU handling a Herd of SBC’s !
Hello Birthy, very nice offer. We want to built a low-power VIM3-cluster in combination with LoRaWAN to send data from several VIM3 with object-recognition to our central server.
Do you have any description of your backplane board? We would be very much interested to get one for testing.
many regards
Heiko Schumann
blu power corporation
Hi - I’m away this weekend (in peaks and hardly any phone signal) but back on Tuesday - will message you then