We’ve had the same issue too; it was brought about by the fact that we tested the original version of the official PoE hat before the Pi Foundation had problems with it and revised the hardware. You’ll see in that post the hardware revision adds the components that you are now finding clash with some of those on the Fin.
The good news is that there are alternatives which we have tested and recommend instead, notably this one:
Thanks for the alternative PoE hat that physically fits onto the Fin, however, we would need to “break out” the power pins of the Ethernet cable to power the Fin, right? Is there a cleaner solution, such as Fin-specific cable that forks at the end with one fork going to the NIC on the Fin, and the other to the PoE header?
I’m not sure what you mean about breaking out the power pins of the Ethernet cable. If you install the DSLRKIT HAT (as linked above) on the Fin, that enables it for PoE with no further cables necessary, just the ethernet cable.
Another option if you’re able to use passive 12/24V PoE, is creating a ‘jumper’ cable that goes from the 4-pin PoE header to the phoenix connector input on the Fin. It has it’s own on-board power regulator, so that connector can accept a 24V input, no HAT required!
Thanks for your prompt response.
Pardon the newbie question, but does this mean that the pins used on the Ethernet cable are passed up to this hat through the GPIO pins, which then power the Fin through other GPIO pins? (I trust that makes sense).
That’s exactly right. The PoE is presented on the additional 4-pin header you’ll notice near the main 40-pin GPIO header, it travels from here to the HAT where it is regulated down to 5V and then passed back down via the 5V pins on the main GPIO header.
I noticed this thread when looking into PoE hats for the balenaFin. I couldn’t find the alternative (DLSRKIT PoE hat) from larger retailers, so I was wondering if it would be possible to use the Raspberry Pi Foundation PoE hat with header extension, and if that would still fit the balenaFin enclosure? Would be nice if you guys have an answer, else I’ll have to get in touch with balena directly I guess.
Hey @mycroes welcome to the forum! I’ve got a Fin here with the PoE HAT and whilst it will definitely work, you’ll also need to find an extension for the 4-pin PoE header as well as the larger 40-pin one.
However, it doesn’t look like it will fit in a standard Fin enclosure, as with the extension the tallest component on the PoE HAT (the fan) sits 14mm higher than the top of the USB ports. I’ve taken a photo below to illustrate this.
One more thing, and I don’t know how helpful or applicable it is, but we publish the STL files for the case on the Github repo, you may be able to modify the design for the phoenix connector ring just to provide a spacer to give extra height for the HAT. Of course, you’ll need longer screws to do this, too
Thanks a lot, that’s two useful answers (although not exactly what I hoped for). I think I’ll might just opt for a normal Pi instead, since I don’t really need any of the balenaFin’s specific features… Thanks again!
