SMETS 2 Meters
Types of Smart Meter
There are two main types of smart meters – the older models known as SMETS 1 (Smart Meter Equipment Technical Specifications) and the newer versions that were rolled out in 2018, known as SMETS 2.
- SMETS 2
- This specification is more advanced and meters were first rolled out in 2018. A more modern communication network is used with these meters and all suppliers will use it this – keeping your smart meter smart when switching suppliers.
Wide Area Network
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. Sometimes your comms hub will communicate directly with DCC and sometimes it will talk through other comms hubs around you to reach a particular comms hub which has direct communications with 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.

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. Communication towers communicate directly with smart meter Communications Hubs in homes.
By 1st June 2020 Arqiva Limited had achieved their maximum contacted 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 (O2) in the rest of England and Wales. This system is commonly used by mobile phones. In a cellular system, geographical areas are divided into regular shaped "cells".
Additionally Telefónica also use local mesh networks to fill in the mobile coverage gaps.
By 1st January 2021 Telefónica had achieved their maximum contacted coverage of at least 99.25% in the Central and South Regions, achieving 99.25%.
2G and 3G networks to close by 2033
The government and UK mobile network operators have agreed to phase out 2G and 3G mobile networks by 2033 in order to free up bandwidth for 5G and future 6G services. This includes Telefónica (O2) who provide the Smart Meter communications for the Central and Southern regions of the UK.
This change will require the replacement of communications hubs on the Smart Electricity Meters in the Central and Southern regions of the UK. To this end the DCC plan to have 4G single band Communications Hubs available in 2023, with dual band to follow in Q2 2024.
SMETS 2 Meter Models
Nearly all meter being currently installed are SMETS 2. If you are wondering if you have a SMETS 2 meter, look up your meter model number in the table below which lists all currently approved SMETS 2 meters.
Manufacturer | Model | ESME / GSME | Type |
---|---|---|---|
Aclara | SGM1415B | ESME | 5 terminal |
Aclara | SGM1416B | ESME | 5 terminal |
Aclara | SGM1422B | ESME | Twin Element |
Aclara | SGM1411B | ESME | |
Aclara | SGM1412 | ESME | |
Aclara | SGM1412B | ESME | |
Aclara | SGM1431B | ESME | Polyphase |
Aclara | SGM1432B | ESME | Polyphase |
Aclara | SGM1433B | ESME | Polyphase |
EDMI | ES-10A | ESME | |
EDMI | ES-10B | ESME | |
EDMI | ES-12B | ESME | 5 terminal |
EDMI | ES-30B | ESME | Polyphase |
EDMI | GS-60A | GSME | Ultrasonic |
EDMI | GS-60B | GSME | Ultrasonic |
EDMI | GS-68B | GSME | 868MHz |
ELSTER | BK-G4E | GSME | Diaphragm |
Flonidan | G4-6UDZV-2 | GSME | |
Flonidan | G4SZV-1 | GSME | Diaphragm |
Flonidan | G4SZV-2 | GSME | |
GWI | G4-MG-SE-GM-V2 FVI | GSME | Diaphragm: Front Viewing Index |
GWI | G4-MG-SE-GM-V2 TVI | GSME | Diaphragm: Top Viewing Index (for semi-concealed applications) |
GWI | G4-MG-SE-GM-V2 DB FVI | GSME | Double Band, Diaphragm, Front Viewing Index |
GWI | G4-MG-SE-GM-V2 DB TVI | GSME | Double Band, Diaphragm, Top Viewing Index |
Honeywell | AS302P | ESME | |
Itron | EM425-UK2 | ESME | |
Itron | FGBB03 | GSME | Ultrasonic |
Kaifa | MA120 | ESME | |
Kaifa | MA120B | ESME | 5 Terminal |
Kaifa | MA329B | ESME | Polyphase |
Landis & Gyr | E470 | ESME | |
Landis & Gyr | E470-5394 | ESME | |
Landis & Gyr | G470-672 | GSME | Ultrasonic |
Landis & Gyr | G470-682 | GSME | 868MHz |
Secure | Liberty 101 | ESME | |
Secure | Liberty Gas 200 | GSME |
ESME = Electricity Smart Metering Equipment
GSME = Gas Smart Metering Equipment.
Five terminal electricity meters have an additional live connector for an off-peak load switched by a timer. The other four terminals are live and neutral in, and 24 hour live and neutral out.
Diaphragm type gas meters have been used for many years. Within the meter there are two or more chambers formed by movable diaphragms. With the gas flow directed by internal valves, the chambers alternately fill and expel gas, producing a nearly continuous flow through the meter. As the diaphragms expand and contract, levers connected to cranks can link to a counter or provide an electrical pulse to measure the gas volume.
Ultrasonic gas meters measure very small difference in time that it takes an ultrasonic pulse to travel with and against the flowing gas stream. A microprocessor can then calculate the gas used. The main advantages of ultrasonic gas meters are that they have no moving parts and are therefore more reliable, and they are more accurate than conventional gas meters.
Semi-concealed gas meters are installed against the outer wall of a building and partially buried into the ground.
SMETS 2 Communications Hubs
The communications hub fits on top of the electricity meter and is owned by the DCC, unlike the meter which is owned either by your supplier or a MAP (Meter Asset Provider) to whom your supplier pays a rental charge. The interface connection to the meter is called the Intimate Communications Hub Interface (ICHI).The comms hub provides both the WAN and the HAN. The Wide Area Network talks to the DCC and the Home Area Network talks to the gas meter and the IHD.
Different comms hubs are used in different regions, see the table below.
CSP Region | WAN Variant | Manufacturer | Comms WAN Technology | External Aerial Port |
---|---|---|---|---|
North (Arqiva Limited) |
Standard 420 | EDMI | Long Range Radio | No |
Variant 450 | ||||
Central & South (Telefónica) |
SKU1 Cellular | WNC (Wistron NeWeb Corp.) & Toshiba | Cellular | |
SKU2 Cellular + Mesh | Toshiba | Cellular & Mesh | 1 Cellular | |
SKU3 SIMCH | Cellular & Mesh | 1 Cellular 1 Mesh |
SKU = Stock Keeping Unit
SIMCH = Special Installation Mesh Communications Hub.
You can see on the table above that the Toshiba comms hub can take one or two aerials. Surveys have determined in advance where these will be used. The table below shows the purpose of the different aerial types.
Aerial Type | % Installs | Radio Use | Manufacturer | Dimensions (mm) | On which Hubs |
---|---|---|---|---|---|
T1 Low Gain |
6% | Cellular | Panorama | 165 x 32 x 20 | Toshiba SKU2 (and SKU3 if poor signal) |
T1 Low Gain |
WNC | 128 x 25 x 17 | |||
T2 High Gain |
4% | Panorama | 372 x 33 x 20 | ||
T2 High Gain |
WNC | 320 x 41 x 17 | |||
T3 High Gain |
0.5% | Panorama | 695 x 25 x 25 | Toshiba SKU2/3 | T3 High Gain |
Oriel | 580 x 100 x 40 |
M1 Short |
0.25% | Mesh | TBA | Toshiba SKU3 | |
M2 Long |
0.25% | TBA | |||
No aerial | 89% |
The table below shows the different frequency bands used.
Frequency Band (MHz) | CHAS | WAN / HAN | CSP Area |
---|---|---|---|
423 | EDMI SBCH, EDMI DBCH |
WAN (includes 'buddy mode') | North excluding Fylingdales |
454 | EDMI DBCH, EDMI Fyl DBCH |
WAN (includes 'buddy mode') | North at Fylingdales |
868 | EDMI DBCH, WNC DBCH, TOSH DBCH |
HAN | North, Central and South |
869 | WNC DBCH, TOSH DBCH (SKU7) |
WAN MESH | Central and South |
900 | WNC DBCH, TOSH DBCH (SKU7) |
WAN | Central and South |
2100 | WNC DBCH, TOSH DBCH (SKU7) |
WAN | Central and South |
2400 | All CHAS Units | HAN | North, Central and South |
CHAS = Communication Hub Antenna Structure,
CSP = Communications Service Provider,
DBCH = Dual Band Comms Hub,
Fylingdales (Fyl) = RAF radar base where frequency interferes with normal Smart Meter communications,
SBCH = Single Band Comms Hub.
The Variant 450 comms hub for the North at Fylingdales is expected to be first available in February 2022.
What do the indicators mean on a SMETS 2 Comms Hub?
On the front of a comms hub there are a series of LED indicators showing the functional status of the metering system. Each LED has a legend as shown below:
CSP Region - Central & South
- SW - Software
- This shows the status of the hub's software.
- WAN - Wide Area Network
- Shows your communication hub's ability to communicate with the DCC and your supplier.
- MESH - Mesh Communications Network
- This light will be on if your meter is communicating through the Mesh network. It will be off if your meter is only using the normal WAN to communicate. The Mesh network has been built to allow more meters to communicate in areas with poor or no WAN signal.
- HAN - Home Area Network
- This light shows the connection status of your electricity meter, gas meter and IHD with your communications hub on the HAN.
- GAS - Gas Meter
- This light tells you if a gas meter is connected to the HAN. If you don’t have a gas meter installed this light will be off.
CSP Region - North
- WAN - Wide Area Network
- Shows your communication hub’s ability to communicate with the DCC and your supplier.
- HAN - Home Area Network
- This light shows the connection status of your electricity meter, gas meter and IHD with your communications hub on the HAN.
What does the flashing rate mean?
The frequency of flashing relates to the status of the function as follows:
- - Power Up
- LEDs are shown without flashing for 10 seconds after power up to allow the operator to see that all LEDs are working.
- - Normal
- A slow flash rate of 1 flash per 5 seconds means that the process is in its normal state.
- - Transient
- A flash rate of 1 flash per 2 seconds means that the process is in a transient state such as making a communications connection.
- - Error
- Fast flash rate of 2 flashes per second means that there is an error. Call your supplier if this does not change after 48 hours.
- - Off
- The communications hub is powered down.
Questions & Answers
- Electricity Meters: MPE Class A
- ± 2.5% at 1 amp
- ± 2.0% at 20 amps.
- Gas meters: MPE Class 1.5
- ± 3%
All meters will have the accuracy class printed on their front face. (Updated: 2022-01-16)
Half-hourly electricity data:
- 13 months of consumption (Active Energy Import)
- 3 months of active energy exported
- 3 months of reactive energy imported
- 3 months of reactive energy exported.
- 3 months of half-hourly consumption
- 13 months of monthly consumption.
Our recommendation would be to let your supplier sort it out, as a communications hub (868MHz) with better reach will be available to suppliers to install with SMETS2 meters where needed from mid 2020. (Updated: 2020-02-09)
Any changes such as new firmware destined for the gas meter are transferred to the "Gas Mirror" first and then sent to the gas meter over time. (Updated: 2020-10-24)
Power quadrants:
- Active energy import (Wh) - this is what we are billed for normally
- Reactive energy import (varh)
- Active energy export (Wh) - this is your useful export power
- Reactive energy export (varh).
For SMETS1 meters the installer will usually test on site and make a decision there and then whether to install. If there is not a sufficient signal they will usually walk away.
For SMETS2 there are more options. The communications are provided by the Data Communications Company (DCC) and suppliers can check that a premises has communications before visiting a site. Once on site they can check with a signal checking device if the signal is strong enough in the meter location. If it isn’t they can fit a number of different aerials to try to boost the signal. If that doesn’t work an external aerial or an alternative mesh communications method is available in some areas. Even then they can leave the meter de-commissioned and ask the DCC to get the communications working. (Updated: 2017-02-01)
However, as this is not a common requirement suppliers have been slow in implementing systems to support it - you will have to shop around for the supplier which can support your requirements. (Updated: 2019-10-21)