[kakarot]

The issue is that as you and others use powerline ethernet, you leak electromagnetic interference patterns back into the powerlines. This buildup of interference from multiple homes creates problems around your area, even if you don't notice it yourself.

[Dylan16807]

So if users had a small low-pass filter installed at their fuse box it wouldn't be a problem?

[revelation]

A low pass filter that can pass 50 kW isn't exactly a trivial device or small in any sense of the word.

[Dylan16807]

Low pass filters don't have the power go through them. It's a capacitor going across the power supply, with a resistor for damping.

[vvanders]

Except unless you have some sort of an impedance follower you'll probably just end up attenuating your powerline networking to the point of not working.

[Dylan16807]

Most of the useful signal in the system is going directly from one circuit to another. The signal headed out toward the power meter is mostly dead, and you might even improve the networking by getting rid of those extra echoes.

Unless I'm mistaken?

[vvanders]

I'd be really surprised if it works that way. I'm not a power systems engineer but I've worked a fair bit on the low voltage side of things.

My guess is that the connection to your house to the service wires in incredibly low impedance, otherwise you'd see all sorts of voltage sags when you used a large appliance with an inductive load(or power tool). So any change large enough to affect the service line is going to go straight into your house. Circuits aren't directional(unless you have a diode or voltage/impedance follower) hence why it would impact the quality of power-line networking.

Additionally any sort of low pass filter(RC, LC or RLC) involves putting a inductor(P) or resistor(R) in series with the circuit(AKA your transmission wires) which isn't simple or cheap.

[kakarot]

Only one way to find out... and I would love to hear about your results :)