Smart Meter (SMETS2) ZigBee Range Extending Inside the Home

MoneySavingAndy

Hi All,

I've just had a SMETS2 smart meter fitted by Lowri Beck on behalf of Avro Energy (although that's not necessarily relevant), and I have a question about increasing the range between the smart meter and the internal usage display. I don't have a problem with the smart meter connecting back to the energy provider, rather it's about how the internal range could be improved - clearly, the obvious solution is to move the display closer to the meter with fewer walls obstructing the signal, but I would prefer to position the display where the rest of my family might see it and actually take notice of our excessive-in-my-opinion energy consumption! Unfortunately, the ideal position is just out of range to achieve a reliable and stable connection.

The Smart Meter has a WNC UBC-TN6 Cellular SKU1 communications hub which a ZigBee certification label on it. I think, after a quick search via Google, that this uses ZigBee at 2.4GHz for the so-called HAN (Home Area Network), i.e. for the communications in the house to the usage display panel. (I believe ZigBee can also operate at 868 MHz, but I don't think this is typical or the case here.)

My question is this: has anyone tried using a ZigBee range extender on a smart meter such as this one to improve the ability to connect to the internal consumer display panel?

I have seen, for example, that IKEA sells this inexpensive TRÅDFRI Signal Repeater (https://www.ikea.com/gb/en/p/tradfri-signal-repeater-80424255/) but I don't know if such a device would simply receive and re-transmit ZigBee signals to boost the range, or whether these smart meter systems have additional security protocols that might prevent such a device 'blindly' relaying signals and working successfully.

I searched for ages to see if anyone had tried to do this but couldn't find any clear answers, so I'd appreciate any advice if anyone out there has tried it.

Many thanks,

Andy.

MWT

The Zigbee repeater has to be able to join the HAN, and right now I do not believe that any repeaters have been approved for that...

It is at least in part a security problem as the gas meter communicates with the gas proxy in the comms hub via the HAN.

There is work in progress to deal with problems in blocks of flats etc. where the meter is often a very long distance from the ideal IHD location, but for now a t least there is no way to boost the signal yourself unfortunately.

QrizB

Reading the instructions for that range extender, it needs to be paired to the existing Zigbee network.

A very brief Google suggests that the root hub in the electricity meter has a whitelist of MAC addresses. This whitelist includes the IHD (and, I assume, the gas meter). You need a password or similar to access the installer meu and edit the whitelist.

You could, I guess, try spoofing the IHD's MAC address and then bridge the data to another network segment with the genuine IHD on it, but if the designers put more than a moment's thought into making the system secure, this won't work.

PS: If you're significantly more of a hacker than I am, Zigbee wardriving is a thing. You could put something together to sniff packets and repeat them. (But I guess if this was the case, you wouldn't be asking this question!)

[Deleted User]

It is supposedly 100% secure which is why only DCC Registered Users are able to add devices to a HAN, or access data from it. For difficult situations (flats, apartments etc), the DCC has approved the deployment of AltHAN.

[Deleted User]

Verdigris said:

On a related subject, what can be done to boost the signal to get smart meters to work in an area with a poor mobile phone signal? I understand that the mobile phone infrastructure carries the smart meter network.

Smart meters which use the Telefonica network also have the ability to mesh with other SMETS2 meters but, as I understand it, the decision to make use of the Mesh is taken centrally based on Telefonica coverage. The basic principle is that a meter that cannot connect directly ‘talks’ to another SMETS2 meter and so on until a mobile connection has been established.

Life would have been a lot simpler had we adopted something similar to the French Linky system which sends data down power lines to a central hub. Also, no IHDs and no right to opt out.

MoneySavingAndy

Thanks for the comments so far - that's not looking too good then as far as my idea is concerned!

Verdigris - appreciate that you have a valid question here, but to improve your chances of helpful discussion it might be worth starting a new thread or seeking out an existing one as the topic I raised was very much focused on the internal comms for the smart meter rather than 'back to base' connectivity over the mobile networks. Cheers.

MidlandsGlory

I am with Avro and had smart meters installed the same. Did you get the Trio monitor? its range is diabolical, there is no spot in our house it can pick up the meter signal (meters are on garage outside wall.)  
Found the Trio has a wifi connection module fitted and I have wifi (via a repeater) in the garage anyway, so you connect the Trio to your wifi, then get the free app from Geo the manufacturer (in the Google store) connects easily via a cloud and a device key code in the Trio. Great! I could even use one of our old smaller redundant Android tablets as a dedicated energy monitor left running this one app. And yes it works..I just leave the Trio in the garage plugged in near the meters that it can connect to them and access it via the cloud/app

But  there is a problem, Geo are aware, Avro are aware but working together they have not been able to fix the issue for months despite deploying firmware updates to the Trio. Namely every few hours some sort of 'reset' signal is sent out by the network to the Trio erasing user settings so the wifi is switched to default off and the connection lost. You have to enable, scan, reconnect and enter the wifi key again every time and its monotonous so I have given up for now.

The uselessness of Both Geo and Avro in sorting this out is pretty appalling. I am fairly sure neither give a damn really. I might as well have kept the ordinary meters, as these smart ones still mean a trip out to the spider factory cupboard with a torch and a notepad for readings, instead of just reading from in the house. Progress? nah.

MoneySavingAndy

Hi MidlandsGlory,

That's really interesting and yes, I too have a Trio (actually Trio II) monitor and have experienced the same problem that you describe of the WiFi dropping (usually after a day or so) and having to be set up from scratch again. It's not too hard to set up using WPS, but I agree that it's tedious and shouldn't be necessary. I did think that was odd behaviour (how on Earth did that get through some basic testing during product development and trials?!) so it's helpful to know that it is a known issue.

I might go for something along the lines you suggest as I have done this for another purpose (related to music in our kitchen!) and have already tried out the app on my phone, but it's still not quite as ideal as simply having the supplied monitor do its job. The irony is that the workaround of using an old tablet as a surrogate display consumes more power (albeit very small amounts) when the idea of smart meters is to encourage behaviours to reduce power usage!

Good luck with the spiders - I'm fortunate in that at least my meter is inside the house!

Cheers,

Andy.

[Deleted User]

MoneySavingAndy said:

Hi MidlandsGlory,

That's really interesting and yes, I too have a Trio (actually Trio II) monitor and have experienced the same problem that you describe of the WiFi dropping (usually after a day or so) and having to be set up from scratch again. It's not too hard to set up using WPS, but I agree that it's tedious and shouldn't be necessary. I did think that was odd behaviour (how on Earth did that get through some basic testing during product development and trials?!) so it's helpful to know that it is a known issue.

I might go for something along the lines you suggest as I have done this for another purpose (related to music in our kitchen!) and have already tried out the app on my phone, but it's still not quite as ideal as simply having the supplied monitor do its job. The irony is that the workaround of using an old tablet as a surrogate display consumes more power (albeit very small amounts) when the idea of smart meters is to encourage behaviours to reduce power usage!

Good luck with the spiders - I'm fortunate in that at least my meter is inside the house!

Cheers,

Andy.

We need to be clear here. There are IHDs and IHD/CAD devices. The latter connect to the Zigbee smart meter HAN and, if you do wish, to your home WiFi. Both operate in the 2.4MHz band. If you are having to reconnect a device using WPS then this a home network problem. As far as the HAN is concerned, the wifi channel is selected by the comms hub when it is installed and as far as I know it cannot be changed.

The CAD of a dual device does not connect to your comms hub. It takes its data from the IHD and passes that back to A N Other via your internet connection. For example, Bulb have deployed the Chameleon IHD/CAD6. The Cad side uses Samsung SmartThings to display data.

The HAN itself is subject to a number of challenges. The major one being foil-backed insulation in cavity walls. This limits the effective range of the Zigbee network. 

MoneySavingAndy

Hi Dolor,

As you say, they may have been some confusion: MidlandsGlory and I were discussing a workaround by minimising the 'HAN distance' by putting the Smart Meter display close to the actual meter to ensure that the ZigBee connection is not struggling because of distance and/or obstructions, and in turn using a secondary display via home WiFi and the app to access the meter information.

The question of the separate WiFi connection issue for this particular unit is almost certainly not a home network problem, at least, not in my case: I have a very stable mesh system (TP-Link Deco M5) that keeps c.20 devices consistently and reliably connected throughout the house with no issues whatsoever, and the smart meter is positioned with a direct line of sight to one of the mesh modules only a few metres away. I would be 99% certain that the smart meter display has some kind of stability / compatibility issue that causes the WiFi disconnection problem - if it is an incompatibility, then this device is the exception rather than the norm as every other WiFi device I have has no issues connecting and staying connected.

A plausible alternative explanation is that the WiFi instability may be because the ZigBee connection fails and there is some interdependence between the two, although that seems odd to me as they are two different communications protocols being used by the device for two different purposes. I'm going to move the display unit anyway and see if at least that works seeing as right now having the unit in the ideal position in the house for us to see it is useless if it won't actually connect!

Regards,

Andy.

MWT

I have trialled the equivalent Bulb system for similar reasons and it does not require frequent resetting of the WiFi details, so I would guess the issue is probably with the IHD/CAD, it is not something intrinsic in the process and probably not related to the Zigbee instability.