Are ethernet powerline adapters a good idea?

[Plexter]

Hi all!

I recently found out about the powerline adapters which allow people to use their home's electrical wiring to transfer ethernet data to different rooms. I'm wondering, is that a reliable way of doing things? As far as I understand that means running data through a mains cable so I'm not sure how well will that work out. I've noticed some people mentioning the adapters saying they've had them without an issue but I still can't quite figure out how it works reliably.

[kripton2035]

it's a luck device ... if it works it's ok, if not you're not lucky ...
you plug it, it works, if you put it in the wall next plug it does not work. that's it.
if it works and you buy let's say a new microwave oven, then it may not work after that, and you have to move the plug to make it work again.
you must have a recent electric installation or for sure it won't work in the plug you want ...
IMHO wifi is far more reliable than powerline adapters (for ethernet)

[madires]

IIRC, there are already a few threads about PLC. Please use the search function 

[miguelvp]

I've been using mine for many years to get ethernet to my home office and had no problems at all.

I got a couple of Netgear HDXB101. Newer ones might be better I'm sure.

Cheap ones probably don't work too well but who knows. Look for reviews before purchasing.

[Kjelt]

The decent ones work pretty well if they are connected on the same group/phase in the house.
Personally I do not use them out of principle , it is a nasty workaround for what you want to do, you modulate a datasignal on top of a high power line.
Which means the data throughput can be influenced on other noise or use of that same powerline.

I did have once a lightcontrol system  that used a primitive powerline principle (x10) and sometimes it just did not work, very frustrating.
Only recommended use of ethernet and limited power is PoE.

[con-f-use]

Overall it worked better than wireless for me.

[NiHaoMike]

They work really, really well if you hack them to run on phone lines.

[wkb]

Power line ethernet is a braindead idea that should never have been allowed on the market: it is a broadband HF band jammer
in disguise.

Anyone interested in shortwave radio reception hates these things with a passion!

[McBryce]

Really sorry then for you Radio guys, but I've been using one for the last few years and it's excellent. I need to get internet into my basement (workshop). The floor/ceiling is reinforced concrete, no holes for new cables and w-lan doesn't make it through. With the powerline I can relay the W-lan in the basement or connect directly with a cable. I've tried several versions / makes. My advice:

- Don't buy cheap, the known name devices really are much better.
- Make sure both devices are on the same phase (if you have a 3 phase system in your house).
- If you have multi phase, try to keep noisy devices (fridges, touch dimmers etc) on a different phase.

McBryce.

[miguelvp]

Power line ethernet is a braindead idea that should never have been allowed on the market: it is a broadband HF band jammer
in disguise.

Anyone interested in shortwave radio reception hates these things with a passion!

At least shortwave radio works fine where they have no internet which is where is mostly needed. The rest will use internet streams instead.

[Matje]

Power line ethernet is a braindead idea that should never have been allowed on the market: it is a broadband HF band jammer
in disguise.

Anyone interested in shortwave radio reception hates these things with a passion!

I would also wonder about the effects on high-bandwidth measurement equipment, say DSOs and stuff. I don't believe every device has filters that good in it's power supply.

I mean Dave checks his new LED lights for possible switching noise, but here people plug stuff into their power lines that is *actually meant* to introduce HF into it, into infrastructure never designed to cope with crap like that in an at least somewhat defined way. It's just crazy, at least for anyone having an electronics lab or a ham shack.

[Kjelt]

The floor/ceiling is reinforced concrete, no holes for new cables and w-lan doesn't make it through. With the powerline I can relay the W-lan in the basement or connect directly with a cable.

Buy a decent hammerdrill or hire a pro. Not a problem for a decent drill to go through 30cm of concrete if you go besides the metal frame 
Using Ethernet powerline is as running water through the gaspipe to save a pipe 

[kripton2035]

Using Ethernet powerline is as running water through the gaspipe to save a pipe

like that one ! =)

[miguelvp]

The floor/ceiling is reinforced concrete, no holes for new cables and w-lan doesn't make it through. With the powerline I can relay the W-lan in the basement or connect directly with a cable.

Buy a decent hammerdrill or hire a pro. Not a problem for a decent drill to go through 30cm of concrete if you go besides the metal frame 
Using Ethernet powerline is as running water through the gaspipe to save a pipe 

That's just a silly comparison and placing a facepalm doesn't make it more true, how are you going to separate the water from the gas? No, Really! I really want to know.

[Jeroen3]

From the Twitters.

Dave Jones ?@eevblog  21 u21 uur geleden
Looked at the neighbors intermittent internet & foxtel problems, saw those ethernet over power adapters & went "We'll, there's your problem"

https://twitter.com/eevblog/status/620156338983714816

[Psi]

They work really, really well if you hack them to run on phone lines.

And even better if you hack them to run on cat5 

[Kjelt]

That's just a silly comparison and placing a facepalm doesn't make it more true, how are you going to separate the water from the gas? No, Really! I really want to know.

I know it is silly but it does feel like that when someone uses this technology only because he has a concrete ceiling and a cheap drill.
But to answer your question about the seperation, the whole (petro)chemical industry uses that for decades, it is called liquid/gas seperators.
examples enough but they are for large scale industrial use, but for household use something like that could be fixed. Where the analogy goes wrong is the pressure difference between water and gaspipes.
http://www.pall.com/main/fuels-and-chemicals/liquid-gas-separation-technology-5205.page
http://www.sulzer.com/hu/-/media/Documents/ProductsAndServices/Separation_Technology/Mist_Eliminators/Brochures/Gas_Liquid_Separation_Technology.pdf

[McBryce]

Well actually, I have a drill that would go through the concrete quite easily, however, I don't own the property, I rent it and the upper floor is also covered in hardwood that is extremely old and expensive. If I was the owner I would have drilled through as soon as I moved in, but that's not an option here unfortunately.
As far as test equipment common mode noise is concerned, my equipment is on a different phase and I don't see any extra noise when it's plugged in.

McBryce.

[madires]

How much impact do filter caps, like X and Y caps in SMPSUs, have on PLC?

[wkb]

Power line ethernet is a braindead idea that should never have been allowed on the market: it is a broadband HF band jammer
in disguise.

Anyone interested in shortwave radio reception hates these things with a passion!

At least shortwave radio works fine where they have no internet which is where is mostly needed. The rest will use internet streams instead.

There are also the radio amateur folks out there.  PLC should have been taken to the back of the shed and shot. 

[Monkeh]

99% of them do not conform to PoE standard, but are compatible.

Let's say, if you use them on a non isolated Ethernet device, it will fry it instantly, but when used with a proper device, it works.

The problem is, if one or both of the peer conforms to PoE std, it will work. If both (power src and drain) doesn't, it won't work.

Use them only with PoE devices, since connecting them to a non-isolated Ethernet device such as some crappy embedded boards will fry one or both of them instantly.

So, the bottom line is if you use it with a tested PoE device, then you can surely use them on a larger scale, but be careful with non PoE devices, since this power supply won't negotiate power requirements with clients, so it will blindly supply power no matter what device you are using with it.

PoE and this thread have nothing to do with each other.

[Howardlong]

I switched from WiFi to homeplug or whatever it's called, and tried two different versions, single phase  in a two bed flat with three APs appropriately channelled. Although Homeplug was more reliable than WiFi, it was still unreliable, possibly due to variable loading on the supply, but it also seemed to coincide with darkness, I assume as the S/N degraded due to ionospheric effects in the evening. Like WiFi, Homeplug never achieved its alleged speeds.

The main reason for "copper" was for a more reliable connection to allow centralised backups of a couple of PCs, and WiFi just wasn't working quickly or reliably enough. But nether was homeplug.

Instead, in the end, I laid that flat CAT6 cable tucked under the carpet edges and under the doors between the three main rooms with switched, and added the three APs covering the entire flat with appropriate channel interleaving. I've since moved the same setup to a three bed flat, and it works very well.

In short, save yourself the agro and uncertainty of a half baked solution, and wire up instead.

[Jeroen3]

but it also seemed to coincide with darkness, I assume as the S/N degraded due to ionospheric effects in the evening.

In the evening all the crap LED and Halogen dimmers get turned on.

WiFi is bad in the evening because the ratio use by the providers, they don't assume all customers get online at the same time. They often use 10:1 ratio of overbooking.
And because in the evening all devices are home and actively used, more overall WiFi traffic in the narrow 2.4ghz band. No vague atmospheric conditions involved.

[Howardlong]

but it also seemed to coincide with darkness, I assume as the S/N degraded due to ionospheric effects in the evening.

In the evening all the crap LED and Halogen dimmers get turned on.

WiFi is bad in the evening because the ratio use by the providers, they don't assume all customers get online at the same time. They often use 10:1 ratio of overbooking.
And because in the evening all devices are home and actively used, more overall WiFi traffic in the narrow 2.4ghz band. No vague atmospheric conditions involved.

I agree it could quite possibly be LED lighting plus dimmers rather than ionospheric effects. Either way, I didn't find Homeplug anywhere near as reliable as anticipated.

I wasn't suggesting ionospheric effects up at 2.4GHz by the way. (Been a ham for 35 years, a good proportion of it up in the microwave bands). While the WAN contention assertion is valid in some circumstances, particularly ADSL, I would expect that to affect performance of wired Ethernet connections as well as WiFi and Homeplug to the internet, and not the speed of backups on NAS on my local LAN in any circumstances. Personally I use cable usually, with ADSL as a backup, and the cable maxes out at about 150Mbps and is fairly static at that with a minimum of 90Mbps occasionally. The ADSL, well, that's like wet string in comparison, but better than nothing at all when the cable fails, which recently it has been doing on an almost monthly basis.

[kripton2035]

with Wifi, you always have the possibility to add one or 2 access points between you and the main wifi, with compatible AP you can effectively extend the wifi network, and so get a nice wifi signal everywhere you want, even under big concrete.
I've never been caught with wifi at a customer's network, you can always have a good signal with some more AP
beware some AP cannot do a network extension (all providers boxes for example ...) so the next AP will not be able to extend the network...
at the contrary I've been forced to leave a homeplug install because the installation did not permit it
so now I simply dont loose time with homeplug and go directly with wifi and always win so far.