Modern metering device (moderne Messeinrichtung, mME), base meter (Basiszähler) and intelligent metering system (intelligentes Messsystem, iMSys) describe three expansion stages of the same technology: from the digital meter to the remotely readable overall system. The terms come from the Metering Point Operation Act (Messstellenbetriebsgesetz, MsbG) and the FNN specification (FNN-Lastenheft) – and are often mixed up in everyday use.
Modern metering device (mME)
The mME is an electronic electricity meter with a digital display. It measures and stores consumption values and provides them locally via the optical INFO interface – it has no remote communication of its own. DIINNO meters such as the DTZ541 (three-phase) and the DDZ285 (single-phase) are modern metering devices.
Base meter (Basiszähler)
The FNN specification uses the term base meter for an mME with a standardised, TLS-secured LMN interface. The difference from a simple mME therefore lies in the prepared connection to a smart meter gateway. The EHZ541-i is such a base meter in the plug-in eHZ design (electronic household meter for plug-in mounting) – with an integrated LMN interface, either optical or as an RJ12 socket; the EHZ541 without the “i” is the mME variant with an external communication adapter (BAB).
Intelligent metering system (iMSys)
An iMSys is created when a modern metering device is connected via the LMN to a certified smart meter gateway. Only then are remote reading, tariff use cases and secure communication with the market participants possible. Existing meters without an LMN interface can be connected in compliance with BSI requirements using the BAB-01 communication adapter.
The three stages at a glance
- mME: digital meter, values available locally via the INFO interface – no remote communication.
- Base meter: mME with a secured LMN interface – ready for the gateway.
- iMSys: mME/base meter + smart meter gateway – remotely readable and controllable.
Frequently asked questions
What is the difference between an mME and a smart meter?
A modern metering device (mME) is a digital meter without its own remote communication. Only when it is connected to a smart meter gateway via the LMN interface does an intelligent metering system (iMSys) come into being – what is colloquially called a “smart meter”.
What does “base meter” (Basiszähler) mean?
Base meter (Basiszähler) is the term used in the FNN specification (FNN-Lastenheft) for a modern metering device with a standardised, secured LMN interface. A base meter is therefore designed from the outset to be connected to a smart meter gateway later.
Does my old Ferraris meter have to be replaced?
Yes, in the long term. Under the Metering Point Operation Act (MsbG), all metering points are to be equipped with at least a modern metering device; for certain groups – such as higher consumption or generation plants – an intelligent metering system is intended. The replacement is organised by the responsible metering point operator.
Can an mME later become an intelligent metering system?
Yes. To do this, a base meter is connected to a smart meter gateway via its LMN interface. For existing meters without a suitable interface, there are communication adapters such as the DIINNO BAB-01, which retrofits the BSI-compliant connection to an SMGw.