Product Overview And Operating Principle; Figure 1: Two-Way Han And Wan Communication - Secure Liberty 100 Technical Reference Manual

2 Product Overview and Operating Principle

Liberty 100 is a single phase, single-element electricity meter that supports both Credit and Prepayment modes
of operation for GB Smart Metering. It is used with a Skyline-i 510 intimate modular communications hub.
The hub is mounted at the top of, and is powered by the meter. It serves as the communication gateway to the
Head End System (HES) via a Wide Area Network (WAN) and other smart metering devices via a Home Area
Network (HAN), and is a data mirror for the gas meter. The modular hub design provides the flexibility to
upgrade or change the meter's communication technology without the need to remove the meter or break
metrological seals. The Skyline-i 510 hub contains GPRS WAN and ZigBee® low power radio HAN
communication modules. The GPRS module connects the meter to the HES over the WAN providing remote
data transfer between the meter and HES on request or when scheduled. The ZigBee module connects the hub
with other HAN devices – Gas Meter, In Home Display (IHD), Prepayment Interface Device (PPMID) and/or
User Access Device (CAD).

Figure 1: Two-way HAN and WAN communication

Additional communication interfaces are provided by an IEC 1107 optical communication port for local
communications and a user interface comprising of a custom LCD display and 12-key keypad. The user
interface allows selecting and displaying data, acknowledging alarms and alerts and provides a means of
manually entering prepayment Unique Transaction Reference Numbers (UTRNs) in the absence of the WAN
and/or HAN.
Commands or changes of configuration can be delivered to the meter in the form of authorised messages or
UTRNs. UTRNs are encrypted codes and are valid only for the meter for which they are generated (see also
Engineering Codes described later).
BGX501-767-R02 Liberty 100 Smart Electricity Meter Technical Reference Manual Page 9 of 116