[ianch99]

Originally Posted by heero_yuy

AFAIK the original ones used the 2G phone data and since that is being decommissioned some stop working. I think the later ones are 4G.

Found this info, quite interesting:

Electricity & Gas SMETS2 Smart Meters

Existing SMETS1 meters are supplier specific and use GSM over existing 900MHz 3G mobile networks (SIM cards).

SMETS2 meters allow the consumer to change supplier and retain full smart meter functionality without needing a change of smart meter.

SMETS2 uses the DCC network, which is accessed via:

North of Lincoln: Arqiva FlexNet 412-424MHz LongRangeRadio WAN
Central & Southern: on cellular 900MHz O2 2G/3G GPRS and Telefonica 869MHz wireless mesh

SMETS 2 Meters

The Smart Metering Wide Area Network (SMWAN or WAN for short) is the name given to the communications network between the communications hub sitting on top of your electricity meter and the company responsible for collecting the data and passing it on to other businesses such as suppliers. This company will usually be the Data Communications Company (DCC) which the government has set up especially for the role of supporting SMETS 2 meters.

Depending on the Communications Service Provider (CSP), which varies by areas of the UK, the technology can change depending on what works best in a local area.

Scotland and the North of England

Long-Range Radio communications (LRR) is used by Arqiva Limited in Scotland and the North of England. The LRR system uses infrastructure and technology similar to that already used for other important national communications networks, such as those for emergency services and keeping lifeboat stations connected. Some 700 communication towers communicate directly with smart meter Communications Hubs in homes using the 400MHz band.

By 1st June 2020 Arqiva Limited had achieved their maximum contracted coverage of at least 99.5%, achieving 99.55%.

Rest of England and Wales

The 2G/3G cellular radio communications network is used by Telefónica (Virgin Media O2) in the rest of England and Wales, known as the Central & South regions. This system is commonly used by mobile phones. In a cellular system, geographical areas are divided into regular shaped "cells".

Additionally, Telefónica also use aerials and local mesh networks to improve coverage. A mesh uses other comms hubs in meters around you to reach a comms hub with a radio link to DCC. This form of communications looks like a mesh when you draw out the possible links between meters and is therefore known as a Mesh network.

So I guess if you have no O2 mobile signal, you might have a challenge?