SMETS2 Quiz Flashcards
(16 cards)
What is an ESME?
Stands for Electricity Smart Metering Equipment - this is the actual electric meter itself
What is a GMSE?
Stands for Gas Smart Metering Equipment - this is the actual gas meter itself
What is the HAN?
Home area network. This is the network that allows communication between the IHD and the meters.
What is the WAN?
Wide area network. This is the network that allows communication between the meters and Octopus (via TMA and DCC)
What is the CHF?
Communications hub function (AKA Comms hub). This facilitates the meters and the IHD to communicate across the HAN, and also to send comms to DCC / Octopus
What is a PPMID?
Prepayment meter interface device. This is the in-home display unit (IHD). This allows you to utilise/switch to prepayment if needed, which you can do through the IHD.
What is the GPF?
Gas proxy function. This lives inside the CHF and is where the gas meter (GSME) sends its information to before it is passed to the CHF and then ultimately on to Octopus / DCC.
What is the trinity?
Commission, configuration and join. All three of these steps must successfully complete in order for the meter and IHD to function, communicate and update successfully.
What is the first step of the trinity?
Commission. If the commission fails, the other two steps will likely fail as well.
What comprises each stage of the trinity, and how many of these are there for each stage?
Service requests. There are 12 SR for commission, 17 SR for configuration and 5 SR for join (34 in total).
What happens if a single service request fails?
The entire trinity process fails.
What is the most common cause of a service request failure?
A timeout. Retrying usually fixes this, and there are plans to implement auto-retrying functionality soon.
How are smart meter communications routed/handled?
All smart meter comms are routed through DCC - a government-appointed company - and the ‘Adaptor’ - a security-audited company through which Octopus’s communications with DCC are routed.
Who is the ‘Adaptor’ for Ocotpus Energy?
TMA
How many devices are installed for a typical dual-fuel MEX. What are they, and what do they each have?
5 devices. ESME, GSME, PPMID, CHF, GPF. They will each have a 16-digit code attached to them.
Explain how instances of incorrect device ID numbers can occur, and what the implications are.
In most meter installations device ID numbers - i.e. the 16 digit codes for the ESME, GSME, PPMID, CHF and GPF - are scanned in using a handheld device given to meter engineers.
Sometimes these devices don’t work, resulting in ID numbers being manually entered - sometimes incorrectly.
Incorrect device ID numbers can cause service request failures which cause the trinity process to fail.
