# Smartmeter interference??



## Cougar Rock Rail (Jan 2, 2008)

Hi all,

Here in BC we're about to get wireless smartmeters jammed down our throats, which I'm not too happy about. Reading the available (and heavily edited!) data on the meters, it looks like each meter transmits to a neighbourhood collector, which then passes the data on to hydro. From what I can find it looks like they will transmit in the 900Mhz band, and do so in short bursts throughout the day. I'm sure their (BCHydro's) agenda is to be able to track our hourly consumption, no doubt so they can bill us at higher rates during the peak daily periods, and less at night. Anyway, I won't rant on about how we're going to get screwed on the rates...I'm more worried about how much interference, if any, I'll get when running my Massoth wireless, which is around 915Mhz. I can adjust that +/- by 1MHz increments but you have to wonder what's going to happen. Have any of you experienced these smart meters yet, and if so, what's your experience been?

Thanks,
Keith


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## Greg Elmassian (Jan 3, 2008)

I know there's a thread on this somewhere... 

I have a smart meter too, and an NCE wireless system on 900 MHz... in fact at the furthest reaches of the layout (the R.J. DeBerg memorial hairpin curve) where I am the furthest from the wireless base station, I am also 5 feet from the smart meter. 

No problems whatsoever and I don't expect any, because it's just a short burst of very little data, so I cannot see how it would be a problem, even if it interfered for 1 or 2 seconds. 

Greg


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## Cougar Rock Rail (Jan 2, 2008)

Interesting, thanks Greg. Is there a collector/hub transmitter anywhere near your house? When you add up all the neighbouring houses, a few collectors....that's what I'm worried about. As you say though, if it really is short bursts it probably won't be a problem.


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## Greg Elmassian (Jan 3, 2008)

I'll look for a hub, but I believe the majority of the transmitting is from the individual meters, sending their information. The utility company is certainly not sending a lot (if any) information to them, it's function is gathering data. When they start shutting off your electricity, that won't take much bandwidth either! 

The only data sent is the time and the cumulative amount of electricity or gas used... very little data... probably no more than once a day for now. 

no way it's anything near a continuous stream.. 


update: PG&E says their meters are transmitting once every 4 hours, 50 milliseconds at a time. 


Greg


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## Cougar Rock Rail (Jan 2, 2008)

Does PG&E say what the exact frequency is of their meters and hubs? 

Keith


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## krs (Feb 29, 2008)

Posted By Greg Elmassian on 26 Aug 2011 05:13 PM 
update: PG&E says their meters are transmitting once every 4 hours, 50 milliseconds at a time. 



I wonder if that is actually true.

It certainly could be and would make the most sense if they use the 900 MHz band, but I just came across a very long and detailed article about "Smart Meter" interference by a system used by one of the power companies in Ontario and they state:


_With respect to recent newspaper articles highlighting potential interference issues caused by our new Smart Meter network, Chatham-Kent Hydro is working actively with our vendor to resolve these issues on a case-by-case basis. As there are many sources of interference on 900MHz devices*, you can identify the Smart Meter signal as a rapid clicking sound.* Although conversation is possible, it is difficult and annoying._

Ref: http://www.ve3ncq.ca/wordpress/?page_id=10


A rapid clicking sound would surely not ne created by a 50 msec burst every 4 hours.

I'm in Ontario as well but with Ontario Hydro. 
We moved to smart meters a bit over six months ago - their system apparently uses the 2.4 GHz band.
I haven't noticed any interference recently but I ended up getting rid of my 2.4 GHz cordless phone system because of its poor performance and switched to DECT.

Don't know if that problem was caused by the Ontario Hydro smart meters but DECT works perfectly - larger range and much clearer transmission.
The only other wireless signal would be WiFi and I assume the 2.4 GHz smart meter systems take that into account or they would have massive complaints.


As to the electricity bill using time-of-day billing - we made no change in the way (and the time) we use electricity and my bill has actually gone down a bit.

Knut


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## Greg Elmassian (Jan 3, 2008)

In every location, something different is possible... In san diego, the gas meter transmits to an access point, on 900 mhz, and the electric meter transmits to the gas meter on 2.4 Ghz. 

All kinds of things are possible, including continuous transmission... but I don't think that is what is happening. 

Just call your power company and have them tell what they are doing. DECT itself does not specify a frequency, but a protocol. I used DECT almost 15 years ago, AT&T liked using it for their cordless phones... 

Also, newer stuff is not analog, but digital with error correction, so it can withstand interference better. 

Greg


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## Cougar Rock Rail (Jan 2, 2008)

I found some data on the hydro website--they are saying there is a total of 45 seconds of sending time per day, with each transmission lasting between 2 and 20 milliseconds. So if we take 11ms ave, that would mean it transmits an average of 2.84 times per minute (and could be up to 15.6 times/min) if I'm doing the math right. That's enough to be a problem I would say if the frequency is the same.

Keith


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## Greg Elmassian (Jan 3, 2008)

45 seconds total... say 11 ms sending, that's 45 / 0.011 = 4090 transmissions of 11 ms a day. = 170 per hour = 2.84 a minute = 0.047348 a second or 21 seconds per transmission so every 21 seconds you get an 11 ms burst. 

With as many times your system transmits the speed command per second, I don't see how transmitting every 21 seconds is a problem. 

Greg


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## krs (Feb 29, 2008)

Posted By Greg Elmassian on 26 Aug 2011 09:06 PM 
DECT itself does not specify a frequency, but a protocol.
Yes, but a DECT phone still has to operate within a specific frequency band as allowed in each jurisdiction.

From the Wiki:
_Frequency: 1880 MHz–1900 MHz in Europe, 1900 MHz-1920 MHz in China,　1893 MHz–1906 MHz in Japan, 1910 MHz-1930 MHz in Latin America and 1920 MHz–1930 MHz in the US and Canada, US DECT and DECT 6 products may NOT be used in the UK as they cause and suffer from interference with the UK 3G cellular networks with unlicensed use of such products being prohibited by UK agencies. As DECT and DECT 6.0 do not operate in the 2.4 GHz ISM band, they are not subject to the interference arising in this band from its use by 802.11b and 802.11g WiFi, and 2.4 GHz cordless phones._

All I was trying to say that when I switched from a 2.4 GHz phone to a DECT phone, the performance became much better, longer range and clearer transmission, which could have meant I was getting interference from the 2.4 GHz smartmeter transmission with the 2.4 GHz phone - except I never even realized this could have been a possibility until I read this post.

Not that I thought that much about possible radio interference when the smart meters went in, I just sort of assumed that they would use a specific band allocated to that service rather than a band already used by dozens of common consumer products.


Knut


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## krs (Feb 29, 2008)

Posted By Cougar Rock Rail on 26 Aug 2011 10:09 PM 
I found some data on the hydro website--they are saying there is a total of 45 seconds of sending time per day, with each transmission lasting between 2 and 20 milliseconds. So if we take 11ms ave, that would mean it transmits an average of 2.84 times per minute (and could be up to 15.6 times/min) if I'm doing the math right. That's enough to be a problem I would say if the frequency is the same.

Keith 

Keith,

I was trying to understand why a smart meter would require 45 seconds of sending time each day.


With Ontario Hydro there are a maximum of three rate periods each day, peak, mid-peak and off-peak - seems to me the meter needs to transmit its reading only at the point in time the rate periods change, ie six times a day.

Even if each transmission is 100 msec, five times as long as they specify, that is nowhere near the 45 seconds per day.
You and Greg are assuming that these meters transmit 24 hours a day in short regular average 11 msec bursts all day long - but why would they need to?


Anyway, I googled to see if I could find more detailed information about the transmission of at least one of the systems - I struck out, but I read about lots of perceived issues other than radio interference with existing devices.


Health risks
http://www.greenmuze.com/blogs/guest-bloggers/3584-smart-meter-health-risk.html
I think this guy is going over the top

Accuracy
http://www.optimumenergy.com/how-to-test-your-smart-meter-for-accuracy/
Hmm...something I should try and check

Surveillance
http://ppjg.wordpress.com/2011/07/09/16975/
They can check when you are having sex. You gotta be kidding!

May 2011 - California Community still up in Arms about them
http://www.smartmeters.com/the-news/2265-californian-community-still-resisting-smart-meters.html
Hope they settled down by now

A fun subject,

knut


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## Cougar Rock Rail (Jan 2, 2008)

Well after watching that surveillance video my wife and I are wondering where we can move to! 

He makes a lot of good points, especially about the value of that data and the lack of controls that are in place. As you say, at this point when they are not billing according to time, there is no need to be transmitting so often yet that's exactly what they are doing--they measured I think it was 1400 bursts overnight in that sleep study. Essentially they are transmitting continuously because while ideally they need the total of say 45 seconds communications to get the data through, that's assuming direct contact with the collector, which isn't always possible so they also communicate between meters....sheesh.... 

 Keith


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## Dwight Ennis (Jan 2, 2008)

I have a hard time believing some of this "surveillance" stuff. The thing is connected to the main power input to the house, not to the individual breaker panel. How does it know which breaker the power is running through, and therefore where you are in the house? What if you leave lights on in rooms you don't currently occupy? How does it know if it's a light bulb, a hairdryer, a TV, a radio, or a stove consuming power? Or your DCC system for that matter? And how the heck can it know when you're having sex? I could be wrong (wouldn't be the first time), but with all due respect, it seems like a lot of overblown "Big Brother" paranoia to me.


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## rmcintir (Apr 24, 2009)

There are a couple different kinds of radio equipped meters. The two I am most familiar with are ERT meters which periodically transmit their readings, typically on 900 MHz unlicensed spectrum to nearby vehicles, and AMI meters which form a network to allow remote readings to be sent back to a head-end. The second type can operate on a range of frequencies but many manufacturers have focused on the 900 MHz spectrum as it provides a good mix of bandwidth, distance and penetration. 

Electric meters have power and therefore can transmit more frequently. Gas and water meters are battery devices and typically must be woke up at which point they transmit their information. They must all meet FCC part 15 sub c power and transmission frequency requirements. Many home power management systems leverage the ERT broadcast and provide the usage information to the household customer. 

Besides meter reading, other uses for these networks exist. They include tamper detection, two-way information to the customer about power usage and pricing, direct load control, distribution automation, remote disconnect/reconnect, and outage detection. Some of these services run on equipment using other frequencies such as 2.4 GHz (Zigbee) and even power line carrier within a home. 

When you hear the term "smart grid" this is the "grid" component providing sensor and control functions. The "smart" is in how the information and control is used both by the company and by the consumer. In generation and transmission constrained areas such as peninsulas, power quality is of paramount importance. When I first started working at a power company, we were the third largest telecommunications company in the state and we didn't have a single external customer. While this is no longer true, our communications needs have still continued to exponentially grow. 

As to trains, I have an ERT meter which is periodically read by a nearby vehicle at my house as do all my neighbors. It operates in the 900 MHz unlicensed spectrum. It does not interfere with my one 900 MHz analog phone and of course doesn't interfere with my own train radio control system which operates at 433.92 MHz unlicensed spectrum. 

PG&E is finishing up an 8 million meter deployment for all their meters. Their meters form a mesh network over 900 MHz unlicensed spectrum. They are beginning to look at more SCADA and DLC type control. Typically meter usage is captured in 15 minute interval data 4 times a day. This of course all depends on the power company requirements. The company can "ping" your meter to obtain an immediate read and determine if you have power. Also, if your power goes out a "last gasp" is sent for outage management.


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## krs (Feb 29, 2008)

After watching the videos (which I hadn't when I posted the links), I'm actually more concerned about the health issues rather than the surveillance. 
But on the surveillance - they are stretching the point, I agree. All the vibratorsI have seen are battery operated so they wouldn't be able to pick that up, so is my electric toothbrush which is another device they mention in the video. 

I don't recall anything in the video where they claim that a smart meter can determine where in the house you are at any point in time - they just infer that you are in the bathroom if the bathroom fan is turned on for instance or in the kitchen if the stove is turned on. 
But I do believe that it is possible to determine which device is turned on, at least to a degree, by analyzing the electric power that is drawn when the device is switched on - not that I really care. 
And even if they can tell that a lamp was turned on at 2:00 am, they still wouldn't know who turned on the lamp, could even have been a timer. 

Knut 

PS: On the surveillance potential - I wonder what the Canadian Privacy Commissioner has to say on that subject. Probably never came up yet.


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## krs (Feb 29, 2008)

Posted By rmcintir on 27 Aug 2011 11:28 AM 
Typically meter usage is captured in 15 minute interval data 4 times a day.


Just to clarify - do you mean data is captured in 15 minute intervals and is transmitted four times a day?


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## rmcintir (Apr 24, 2009)

15 minutes with 4 bulk transfers per day on the AMI network. The ERT meters operate differently and can remotely send that data when requested. This is for time of use and various commercial rates. Technically this could also be done for residential, it depends on the rate plan.


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## Dwight Ennis (Jan 2, 2008)

BTW, we got a smart meter installed a few months back. I've noticed no discernable difference in my utility bill.


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## Cougar Rock Rail (Jan 2, 2008)

Sure is an interesting subject, the more you look into it--thanks for all the input guys. A few years ago I was telling my kids that someday they will have something like a decoder in each electrical device, with it's own address, and with it's own priority on the grid. So in the event power is being restored or restricted, "they" could start up only the electrical devices they wanted, for example hospitals etc. Looks like we're not far off but they are going to use bluetooth devices instead I guess. 

Keith


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