X10 Community Forum

🔌General Home Automation => Automating Your House => Topic started by: Oldtimer on May 20, 2013, 12:53:34 PM

Title: X-10 Interference From Ethernet-Over-Powerline Question
Post by: Oldtimer on May 20, 2013, 12:53:34 PM
There are a number of products on the market that allow you to extend your LAN over the powerline.  Has any one had any experience using these in conjunction with X-10?  I'm concerned that they may generate the same kind of X-10 interference that powerline based wireless intercoms do. The product names I've looked into are:

Trendnet Powerline 500 AV Nano Adapter Kit
ZyXel PLA4205 500 Mbps Powerline Gigabit Ethernet Adapter
Actiontec 500 Mbps Powerliine Network Adapter Kit
D-Link DHP-501AV PowerLine AV500 Adapter Starter Kit

If your experience is with some other brand please include its name in your reply.  At the frequencies and bandwidths involved in these devices the problem may well be manufacturer specific.  We've already run into that between an active Roku box and X-10.
Title: Re: X-10 Interference From Ethernet-Over-Powerline Question
Post by: dhouston on May 20, 2013, 03:01:43 PM
I doubt you'll have a problem. These devices use much, much higher frequencies than X10 devices can receive as well as using far more sophisticated modulation techniques. They also adapt to noise by shifting frequencies.

I have a Roku3 and have seen no interference with X10. Can you describe your experience. Perhaps yours has a noisy switching power supply.
Title: Re: X-10 Interference From Ethernet-Over-Powerline Question
Post by: Oldtimer on May 21, 2013, 11:54:11 AM
I doubt you'll have a problem. These devices use much, much higher frequencies than X10 devices can receive as well as using far more sophisticated modulation techniques. They also adapt to noise by shifting frequencies.

I have a Roku3 and have seen no interference with X10. Can you describe your experience. Perhaps yours has a noisy switching power supply.

Thanks for the Ethernet-Over-Powerline comments.  I'll wait a while to see who else posts and then try one.

As to the Roku - its not the power supply, that's plugged in all the time.  The interference only occurs when someone is actively using the Roku box via WiFi to watch a movie on Netflix, which is the only service we subscribe to.  I've been busy with other projects so I haven't checked out the power line noise level yet but will post more info on here when I have it.
Title: Re: X-10 Interference From Ethernet-Over-Powerline Question
Post by: JeffVolp on May 21, 2013, 12:02:59 PM
As to the Roku - its not the power supply, that's plugged in all the time.  The interference only occurs when someone is actively using the Roku box via WiFi to watch a movie on Netflix

It might still be the power supply.  The noise from that Cellet cellphone charger varies greatly depending on how much current is drawn.  With no load there is a little burst of noise at the peak of the AC waveform.  When heavily loaded as it would be when charging a battery, the noise persists over the entire AC waveform.

The same might be true with the Roku power supply when the unit is active.

Jeff
Title: Re: X-10 Interference From Ethernet-Over-Powerline Question
Post by: dhouston on May 21, 2013, 01:06:20 PM
As to the Roku - its not the power supply, that's plugged in all the time.  The interference only occurs when someone is actively using the Roku box via WiFi to watch a movie on Netflix, which is the only service we subscribe to.
I don't recall which thread it was (it was about power supply noise) but I posted a link to an oscilloscope screenshot showing the current drawn by a switching power supply. Basically, they only draw current when the input voltage exceeds the voltage on their storage capacitor so you'll see current spikes at the peaks of the switching frequency (frequently near 120kHz). This creates a lot of harmonic distortion and will certainly be worse when the device is loading the power supply.

As for WiFi, it's even more unlikely that it's the direct cause of the noise. Almost all of my computer and other electronic gear (about 10 devices) use WiFi with no apparent effects on X10. The WiFi frequency is even higher than that used for ethernet over powerline.

EDIT: Here's the thread...
Title: Re: X-10 Interference From Ethernet-Over-Powerline Question
Post by: Oldtimer on May 31, 2013, 08:55:20 PM
I doubt you'll have a problem. These devices use much, much higher frequencies than X10 devices can receive as well as using far more sophisticated modulation techniques. They also adapt to noise by shifting frequencies.

I have a Roku3 and have seen no interference with X10. Can you describe your experience. Perhaps yours has a noisy switching power supply.

Thanks for the Ethernet-Over-Powerline comments.  I'll wait a while to see who else posts and then try one.

As to the Roku - its not the power supply, that's plugged in all the time.  The interference only occurs when someone is actively using the Roku box via WiFi to watch a movie on Netflix, which is the only service we subscribe to.  I've been busy with other projects so I haven't checked out the power line noise level yet but will post more info on here when I have it.

I finally had the time to check out the possible interaction between the Roku box and X-10.  There was NO interaction.  There was coincidental interaction between a fluorescent type lamp and X-10 at the same time the Roku box was on. Sorry for the red herring. B:(