Powerline networking, using existing electrical wiring, has been around for many years. Indeed, over the years, some video surveillance providers have offered it as an alternative to coax, category cable and wireless. However, it has never really taken off.
Now Comtrend, adopting a more recent powerline standard, is promoting powerline networking specifically for video surveillance use. Indeed, the company's PG-9172 Series offers a range of video-appealing features like PoE, multi-adapter networking, and even support for coax cameras:
But how does powerline work, and is Comtrend's product a good alternative to running network cables? We examine product claims and identify strengths and weaknesses inside.
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This reminded me of Aboundi, who used to have a demo RV that was at ISC West and ASIS every year, until it wasn't. They were big promoters of powerline networking products, but at some point in the last several years must have gone out of business.
They had some interesting form-factors, like this combination powerstrip/network switch:
I think Comtrend may be the next Aboundi.
Has anyone ever tested any Powerline equipment? I have always found it interesting but more of a novelty. I would debate it for my home if anyone had moderately positive feedback. Any problems with latency?
I use it to connect a recorder in my garage to my house. Actually I've done that in two houses, now that I think of it.
In house one, which was built in 1908, and honestly probably still had a bunch of old knob and tube wiring and very little grounding, it was bad. Maybe 5Mb/s, and frequently dropped. It was the only option other than wireless...also not a great option for a 1908 house, so I went with it.
In house two, which is from the 60s and was rewired at some point, it works great. It seems no different than a Fast Ethernet connection to me. It's supposed to be 600 Mb/s, which I'm sure it is not, but it's been totally reliable and more than fast enough to view a couple cameras out there. It may be a bit more latent but I wouldn't say it's at any unusable level. I haven't measured it.
I have always wanted to try it, but never got around to it. I do have a situation where it could be handy. If I can find some adapters for not too much money, I may pick them up and give them a trial run.
Edit: $112 CAD for each POE adapter, $162 for the non POE for some reason, on amazon.ca not so sure I will be giving this a trial after all, haha.
I have 2 powerline setups to connect NVRs to the internet that have ran for a year or more with no issue. Both systems are small 4 cameras each and the homeowners only use the mobile apps to view live feeds. In the future I may move one of the test rigs over to one with 12 or more cameras and view full feeds.
We use PowerLine in the past to connect intrusion panels to the internet when the customer didn't want to pay for the tech to run the cable. We have several out there that have been running for years without failure. I'm not sure I would use it in a critical security application for a camera. I could see using it to get internet (or internet devices) out to a barn or shed that's connected to the house by electrical lines.
On the issue of not meeting bandwidth claims, Comtrend has this comment. (I added this section to the post above):
Comtrend Responds To Weak Bandwidth
We asked Comtrend why even otherwise positive reviews cite fractional bandwidth throughput, often far below the 1,200 Mbps rating claimed. They responded:
"The PHY Rate of 1200Mbps is a measurement from an environment in the most ideal line condition. The performance of each node is influenced by the wire condition, electrical noise present between other nodes, number of outlets between points, and how many nodes are present in the network.
Remember that the G.Hn is not concentrating on PHY rate measurement alone. The product provides stable usable throughput to provide the best HD Video streaming even in the most difficult environment."
In essence, Comtrend is saying that if a Powerline network is setup, designed, and used specifically for data, the bandwidth levels are higher. But as with all Powerline networks, this is not a realistic use case for the equipment, so actual throughputs is lower, sometimes drastically.
We've never used these but always been curious about them. Do the two units have to be on the same circuit breaker? Or just the same panel? Do they use the ground/neutral wire for TX/RX? or Hot/Neutral?
I believe they have to be on the same phase. Back in the early 2000's I used to share my internet with my next door neighbor using this technology. So I know it works through power meters also.
This product works like a champ. Used it a few times!
I’ve found the technology works well generally except when plugged in to power bars or GFCI outlets as the filtering blocks communications. Sometimes it’s a problem if modules are on different phases
I have used powerline adapter few times
Working good so far
Does anyone remember Visual Gate out of Canada?
Anthony, I do. I remember them way back when. I actually thought it was promising. Obviously I was wrong.
Related, do you know what happened to them?
I repped them. I never got paid, they just just disappeared. They never even asked for their demo gear back.
I have a set of Zyxcel power line adapters in my tool bag. Use it to get network to the places on job sites where there isn't network available otherwise. I would rate the technology as solid, on newer wiring it has descent throughput and is reliable.
There are definitely issues if both of the units are not on the same phase, I have also noticed that some of the new AFCI breakers mess them up. There was one building were I used to be able to use them and then the owner replaced all the circuit breakers in the building with AFCI type breakers and the adapters quit working.
What happens with these when there is a blackout? We go to the effort of fitting UPS in CCTV & battery backed power supplies in the alarm & access world. All a bit pointless really if your connectivity link (EOP) fails during power failure
Interesting question. I'm betting the link dies as the internal electronics providing the carrier are powered from the main AC. But theoretically, if the electronics were backed up, and the wires still there, it ought to work.. even better with no AC noise.
Has anyone used these for access control? Door Controllers use hardly any bandwidth compare to video. You would think powerline would have more adoption in that area.
As long as all of your door controllers are fully intelligent & not reliant on any other devices for operation / access decision making then this is a much better application than video or security reporting. Typically low bandwidth & not very time dependant, so high latency / low availability is not really an issue.
I wonder if this would work on 220V Light poles, get an electrician to install stepdown xformers on both ends (Circuit breaker panel and pole), put everything in a NEMA enclosure out at the pole.
Has anyone done this?
Hi Cary - I don't think so. As soon as you go through a transformer you lose connectivity and thus signal.
I think if it is a 4 wire circuit, an EC could derive a 120V outlet at the pole and the Breaker panel without a transformer., but I'm not an electrician, hoping someone of that trade would chime in.
While cabled video subnets may support encryption, HTTPS, or VLANs, those policies will not apply to Powerline networks and must be separately managed, if they are even possible.
Disagree.
Powerline supports encryption as well as “cabled video subnets” do. Which is to say that they are both unaware of it since they operate at lower ISO levels.
Put another way, a stream that is HTTPS encoded by a camera will remain encoded until it reaches the destination IP, regardless of the intervening transmission media.
I used to subcontract for a gentleman that used quite a few of these. They are unreliable, drop off the network during simple things like power outages and overall cause unnecessary headaches. I would advise against using them for anything serious.
Thanks for the field report. Are the ones you mention Comtrend units, or are they similar powerline converters?
They are unreliable, drop off the network during simple things like power outages...
That’s funny.
They should be like “Yo, we got the cable all to ourselves!”
The ones I remember using were sold at ADI and I think they were comtrend. I am not 100 percent sure. I will say that at an ISC East show there was an independent company that claimed to have a stronger model. They knew the ones we were using were unreliable.
My pops swore by a set of little devices by the name of Plug-Link made by Asoka. Probably about 10 or 12 years ago that the AT&T techs would issue off the service vans to customers that were not open to techs drilling a hole literally from the inside finish of the house through to the exterior followed by a smudge of silicone and into the residential cable tray a.k.a the gutters. Anyways they worked great for what they were, they had a 10\100 RJ-45 on each unit and boasted an 85Mbps throughput, they certainly get the job done, especially useful in cases where you need a connection to an out-building which has power derived from the same electrical service where your uplink is located.
As an Electrician, ill tell you that a transformer anywhere between 2 devices that communicate by whistling a frequency through the lines WILL disrupt your signal if not isolate it all together, and yes both devices must be on the same phase, on the same electrical service\derived system. I don't see how arc-fault breakers could disrupt the communication between devices like this, as there is a solid connection all the way through the innerts of the breaker itself though I can't speak for the signal\frequency itself tripping the breaker i.e. simulating an arc\or being detected as such. Obviously your limited to how many of these you can use at the same time (1 per phase) but in a pinch they certainly have their place. I'm not sure where the expectation came from that these should work during power outages but then again, what does work during a power outage.. Also we could dive into building electrical harmonics and power factor and all kinds of other variables that may adversely affect devices like this but in all reality, if you are looking for reliability, just run a wire. If your in a pinch and out of options, these are great alternatives.
