Smart meters blamed for Wi-Fi, garage opener interference Smart meters issued by an electric utility in Maine are interfering with a wide range of customers' electronic devices, including wireless routers, cordless phones, electric garage doors, and answering machines. The Central Maine Power Company has received complaints from more than 200 customers since the meters were installed …
Complain all they want, they have no reason to expect a solution. The 2.4 GHz band is deliberately unlicensed. Stay on the allocated frequencies and under the permitted power levels using FCC certified equipment and thats that. There is no guarantee or right of non-interference bandwidth.
I think it's not unreasonable to call foul when a public body decides to dump an extra 1/4 million devices into an already notoriously overcrowded band.
Id bet a penny to the pound this was a case of bean counters deciding that that free, unlicensed, and available as off-the-shelf transponder modules bit of spectrum was by far the cheaper, and thus better option. Sod the engineers with their petty concerns about "reliability" and "responsible use of a public resource".
So the meter should look around for a free channel when it needs to transmit, rather than stomping all over a channel that's already in use.
Ok, that's not going to help with the garage door openers and such, but cacking on an in-use Wifi channel? Fail.
The free-for-all in 2.4Ghz only works if everyone plays nice.
Never mind the 2.4GHz tinfoil hat issues (though I'd be interested to know where the other end of the link is, and how well its two way communication would cope with a couple of 2.4GHz videosenders permanently sitting on the meter's preferred channels).
These smartmeters feature "remote off" capability (according to the linked FAQ).
In order for that remote-off capability to be useful, it has to be jamming-resistant (otherwise, for example, the aforementioned videosender reduces the smartmeters ability to switch off when commanded).
How do they achieve that jamming resistance?
One obvious and simple way would be for the smartmeter to default to off if it doesn't receive a routine "keepalive" signal from HQ.
I don't want that. Do you?
I don't know if that's the way these things are designed (it'd be part of my design if I wanted reliability; one aspect of that would be jamming resistance). Do you know if that's the way these things are designed?
I happen to work for one of the largest meter producers and also happen to know how these things are designed.
The R/F component of the meter is typically customer specified (i.e. whatever they want we slap it on the meter, LPR, ZigBee, WiFi, EDGE, GPRS, 3G, PLC, you name it). So this option is what the utility thought would work best for their usage scenario.
WRT the disconnect part, you can't work on a "keep-alive" signal. That is by law. All error states (interference would be one them, age-related inaccuracies is another) must work in favour of the user. Hence in a case of a meter being "offline"/unreachable the meter will continue to allow power. In such a case a manual disconnect would be required, if warranted.
However, the basic premise still holds, ie most meters can be managed remotely. So while on-site engines will not be removed from the picture they will now manage much fewer incidents.
Anon for obvious reasons
Speaking as an RF newbie:
What equipment or other tools would I need to investigate this in regard to my own house's smart meter (in a different utility's clutches)? I suppose I should start by checking whether it has an FCC ID printed on the case.
Links to helpful do-it-yerself FAQs etc.?
I begin to wonder if some of my in-house WIFI flakiness is induced, not just inherent in the protocol...
I'm on of those affected by these infernal devices*.in Maine. 1 1/2 months so far and I haven't noticed any problems (with the electricity bill or wireless). The Internet has been a bit slow, so maybe, oh, wait, I use Ethernet.
Wireless interference is something people should have been told about, but that would have helped feed the animals.
200 complaints about something would normally be a lot. But, it's not so much on a topic where people have been trying to stir up controversy.
* That was irony
Not enough detail about just how wireless is used in these devices. Is that for drive-by meter reading? So who pays for the power to continuously emit 2.4GHz? Surely listen, turn-on, reply is the correct model to go for, rather than continuous transmit? And don't the meters interfere with each other?
WiFi protocols+devices are designed (to an extent) to coexist with each other in the same frequency range, and TCP/IP (UDP/IP, etc) adds a certain amount of robustness.
Classical analogue videosenders have no such capability. Turn on transmitter, modulate video data onto continuous 2.4GHz stream. Hope no other device nearby is badly affected.
Choose your weapons carefully. Certainly more carefully than these smartmeter people appear to have chosen.
I assume the smartmeters are designed/manufactured/supplied by an external company, not the electricity company itself. Anyone got the details?
By definition, an electricity meter is very very close to an actual transmission line: the electrical supply cable. There seems no reason the smart meters can't send their data back down that. If that's too hard, why not piggyback on the phone line? Wireless seems to have become hopelessly fashionable, in defiance of its real engineering parameters. Wireless is good for some situations, mediocre in others, and downright bad in many. This looks like one of them.
I've always wondered about these smart meters using wifi. In some locations wifi is all but unusable, it's pretty damned poor at my house but I've been places where it's a lot worse. So I've long suspected that using the unlicensed wifi frequencies for these boxes was a pretty stupid idea. There are plenty of locations where they will find it difficult to operate them effectively.
Rather than using these frequencies the utilities should licence their own bandwidth to ensure they will operate properly and not interfere with other equipment.
In all of the issues discussed on the forum, none touch the most serious topic. Security...
"Security experts have also warned that smart meters are susceptible to hack attacks that could potentially take down the power grid. ®"
Now I don't wear a black or white hat, but when you consider that there have been a couple of reports of water systems now getting hacked in the US, you have to wonder if the smurt er smart meters are a good idea....
Do you *really* think the UK will buy a specific "Designed for UK" smart meter?
Of course not.
Yes they are normally supplied by outside companies (Landis and Gyre IIRC are quite prominent).
*Some* attempts have been made to check their security (reported by El Reg) and showed them pretty vulnerable (no authentication, ID #s sniffed etc. Shades of the remote adjustable insulin pump). but then the meter mfg stopped making samples available to the testers.
Here's a thought. Do the penetration testing *before* you roll out.
I live under the cloud of PG&E (Pacific Gas & Electric -- northern California). So when I went to investigate my meter I ran across some city of SF documents addressing these concerns (sorry, didn't save URL).
In sum, from memory: the system rolled out in SF uses 2.4GHz but not WIFI. Each per-meter unit emits 4 packets a day, each packet is some number of milliseconds (<100 I think). Transmission power is <1W. Transmission power and length are hard-limited by running the transmitter off of a slow-charge capacitor. Several hundred thousand per-dwelling transmitters. The receivers are on towers (existing power or phone poles), 77 of them in the city. They receive the individual transmissions and also send (at 2W) a once daily time sync packet. Collected data is transmitted over a cellular radio, not particularly different from a random person talking on a cell phone, except it's 20' in the air; data transmission could run for as much as 4hr/day per receiver, though that's a worst-case-in-many-ways calculation.
So, nothing to worry about *here*. Which is not to say that designs elsewhere couldn't be much worse.
Oh, and that's nothing to worry about in regards to interference, bandwidth use, personal irradiation etc. Feel free to freak out about whether they're reading your usage accurately or are all part of a Big Plot...
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