Safe way to interface directly with HomePlug / Powerline

filtermainspower line communicationsignal

I'm looking to do some research into the actual messaging used by powerline adapters. I'm aware of the standards, but I'm specifically looking to see where real devices deviate from the standard, and how they might be played with from a security standpoint.

What's a sensible way to interface with the powerline adapters safely? I envision some kind of high-pass filter on the mains which pulls out just the HF components (>1MHz), but then I'm not entirely sure what kind of voltage levels the resultant signal would come out at. I'm looking to translate them down to save levels (e.g. ±1V) for analysis.

Is there a simpler option, perhaps a chipset that can be interfaced with from a microcontroller that supports direct messaging rather than an Ethernet abstraction?

Best Answer

Intersting. I'm assuming you want to see beyond (further into) what you'd get out of a vendor's silicon solution. If one knew the specific protocol at work, then I'd go looking for the datasheets of that silicon vendor's chips, & in there (or in related AppNotes) you'd likely see reference designs that'll show you what kind of mains line interface is recommended (voltage transformer, current transformer, filtering, AC-coupling, etc).

And for (a) the sake to saving you from constructing an interface yourself AND (b) to leverage the relative safety of the vendor's existing design rather than having to get a bunch of mains safety stuff right yourself, perhaps hack into a vendor's product to get at the analog signals before they disappear into their silicon.

Naturally all the warnings and safety recommendations about working with deadly voltages applies here. Highly recommended is to seek out someone who knows how to handle mains safely to get get you started. And put an Earth Leakage Circuit Breaker between your test rig and the wall socket. etc etc etc.