One for the smart meter sceptics

It's silly that there's a hard cutoff. If there's no 400MHz signal north of the line, let installers fit a comms hub using mobile signals. If you're south of the line and have good 400MHz signal but no mobile, use 400MHz. (probably area limited by distance from transmitters). It would also negate the need for the special Fylingdales frequency - just put everyone near Fylingdales on the mobile network.

Theo

Why does it say mobile signals can be improved with an aerial but nothing about improving radio signals that way?

(Yes, I know mobile signals are technically a kind of radio signal.)

For the mobile network comms hubs there's a variety of different antennas they can fit depending on the location. Do the UHF versions also have different antenna options?

Also I think the comms hubs can make a mesh network to get signal via the neighbours' meters as well as sending directly. Do both kinds of comms hub do that?

Theo

We live North of the dividing line and have never had problems with communicating with the supplier even though we live in the Pennines. Our problem has been the gas meter communicating with the electric meter right next to it. After many attempts at software upgrades we finally got them to change the meter and so far so good. Apparently according to the meter changer it was the battery that was knackered before its time.

No, the ones on the Arqiva network have no option for an external antenna, only the built-in (and unchangeable) one.

I am guessing that that is the same form of communication as is used between gas and electricity meters - and even that can be difficult. The separation of houses (particularly in poor signal, countryside areas) likely means that that won't work in many cases.

It's the BBC. "I don't listen to the BBC for the same reason I don't drink out of the toilet."

I doubt the BBC does...

I think simply because the mobile data comms units used in the south have a socket for an external aerial, whereas the “radio” ones don’t.

Tim

It seems like there's quite a menu of options for radio/antenna/mesh choices in the south, but just one comms hub/antenna option without mesh in the north:

Theo

Thanks.

For 2G/3G comms hubs in Central/South region, I think there are SKU1 comms hubs, with an internal aerial and no aerial socket.

Then there are SKU2 comms hubs which come with a small "T1" aerial, but can be upgraded to a longer "T2" aerial, both for indoor use.

Failing that, there is an option for a "T3" outdoor aerial, but that needs booking for a special appointment.

For Arqiva comms hubs in the North region there only seems to be one SKU, and no options for other aerials at all.

That shows there is a second type of hub for the North region, made by Wistron/Toshiba using mobile phone signals (still no aerial socket).

Which one is that? The only Wistron (WNC)/Toshiba I can see there (SKU1) is for the south/central region.

Theo

My eye was confused by the table, because the 1st and 2nd rows of the

No-one mentions the obvious "shitness" of smart meters. (They didn't in the recent Channel 5 programme either):

1. They don't measure the consumption of individual appliances;
2. They don't tell you the average consumption of an individual appliance (such as a fridge);
3. They don't enable you to measure the total energy consumption for a particular process e.g. to compare cooking a jacket potato in an oven or a microwave, or cooking a stew entirely on the hob as opposed to starting on the hob and finishing in the oven;
4. They enable suppliers to switch your power off remotely, "by mistake";
5. They enable the suppliers to charge different rates at different time, not just in an easy to understand way like Economy 7 but also to bump up the rate just when you want to cook dinner.

Ah, what you want is a MAGIC meter. Maybe you need to tone down your expectations a little?

Seriously, until every appliance comes with built in power monitoring and comms, there’s no way a supply meter can differentiate who’s using what and when.

Until then, a meter that can monitor half hourly consumption and enable power companies to offer smart tariffs that offer consumers much more control over their energy costs seems like a good thing to me.

Nothing stopping you sticking with dumb tariffs.

Tim

They measure the whole house supply - just like any other meter.

as above

as above

Possibly - I've had mine for over 5 years without this happening

Highly beneficial for me - I can charge my EV at a cheap rate

To measure individual appliances, you use one of these. This is a "miniature smart meter" which is just as accurate (1%) as your household smart meter is. It uses two 500KHz sigma-delta converters, to convert the voltage and current waveforms to digital form, so the meter box can do the math equations and work out W (watts), VA (VoltAmperes), PF (Power factor). On an electric fire, the power factor is 1.0 (in phase, non-reactive load).

For an electric fire, you can plug in any electric fire up to the current flow limit. Measure the values for ten seconds or so. Then turn off the electric fire and disconnect it. This prevents thermal damage to the shunt inside the meter.

While the meter has a 13 amp rating, it's best not to run it at 12.999 amps for a year or so, because that can cause the solder to melt underneath the shunt :-)

If you put a more-capable shunt in it (more cool-running), the sensitivity of the ampere conversion circuit must be cranked up, and it is harder to do the design for that. while they know how to fix this, they're not changing the design. If they want 100mV full scale across the shunt, nobody is changing the circuit to 10mV full scale, and delivering

So the design of the miniature meter, is ideal for refrigerator and IBM PC. The numbers should be good to 1% . For an electric fire, a ten second reading should verify what you already know about electric fires :-) Their consumption is proportional to voltage, if your line voltage is too high, your electric fire draws too much current. This is not a fault of the electric fire. Electric fires would be too expensive if they were fitted with "regulation". It is the job of your power supplier to implement "regulation" and deliver the exact right voltage. (I'm saying that for the benefit of my power company, who do not know this!)

Paul

But if it's approximately 423MHz signal, it should have good penetrating power.

The box has WAN and HAN. The HAN (Home Area network, sorta like a Bluetooth with some kind of pairing or something) could be 2.4GHz Zigbee, while the WAN could be the 423MHz thing using a PCB antenna. You will need to review the lighting pattern on the WAN LED, for some idea of what it is doing (searching for signal).

https://anengineersview.tech.blog/smets2-is-there-anybody-there/ There could be more than one reason for this scheme to fail. The WAN could be a 1 watt transmitter and I presume the PCB antenna has a single lobe sticking out the front of the box. And that lobe should be pointed at your nearest broadcast TV antenna tower (where the 423MHz receiver *could* be located). Perhaps rotating the comms box, would be enough.

The article above, one of the proposals, is to retrofit a Slim Jim antenna, cut to 423MHz length.

This isn't enough detail for the passive scheme, but maybe someone in the audience can make sense of it. There is one picture on this page, of an antenna seemingly taped to the unit, and maybe there is a balun hiding under the black tape. But what is outside the house, on the other end of the coax cable, dunno. Sometimes, with antennas, details don't matter. For example, at 200MHz UHF, it doesn't matter what shape a thing is, how poor the impedance match, signal just floods in. It's rather awful actually. At other frequencies, you have to behave like a radio engineer :-)

Here's what some of the base stations look like for the north.

Ringway Manchester (YouTube): "Why Did This Appear On My Street?" -