
A3 ALPHA Meter/Collector PG42-1005A
2July 2003
The A3 ALPHA meter/collector is the communications point between the
EnergyAxis System and the local network of REX meters that are registered to
the meter/collector. The EnergyAxis System communicates with the A3 ALPHA
meter/collector using a standard telephone line. The A3 ALPHA meter/collector
then communicates with its registered REX meters using a 2–way, 900 MHz radio
frequency network. The A3 ALPHA meter/collector is responsible for various
activities within the network of REX meters, including the following:
■reading and storing the billing data from each REX meter on a periodic basis
■reading and storing the load profiling data from a configurable number of
REX meters on a periodic basis
■notifying the REX meters to perform demand resets based on a schedule
from the EnergyAxis System
■reading and storing the previous billing period data from REX meters after a
demand reset has occurred
■notifying the REX meters to perform season changes based on a schedule
from the EnergyAxis System
■reading and storing the previous season data from REX meters after season
changes have occurred
■synchronizing the REX meters to the system time and TOU day type
■distributing TOU rate schedules to the REX meters
■reading or sending commands to an individual REX meter on command from
the EnergyAxis System
■performing other network maintenance tasks
■reporting the billing and load profiling data back to the EnergyAxis System
General Description
The A3 ALPHA meter builds upon the strengths of the existing ALPHA meter
designs. Like its predecessors, the A3 ALPHA meter uses Elster Electricity's
patented digital measurement techniques that offer high accuracy, repeatability,
and low ownership costs. In support of open architecture standards, the
A3 ALPHA meter is the first Elster Electricity meter with full ANSI C12.18,
C12.19, and C12.21 communication protocol support.
To function as an A3 ALPHA meter/collector, an A3 ALPHA meter requires the
following two option boards:
■internal telephone modem (ITM3) with optional outage reporting capabilities
■internal LAN controller (ILC1) option board
The ITM3 option board connects to the A3 ALPHA meter using the 20-pin
header (J4) on the meter circuit board as shown in Figure 1. The ILC1 option
board connects to the ITM3 option board using the 20-pin header (J5) as shown
in Figure 1.
An A3 ALPHA meter/collector has a 4-conductor telephone cable exiting the
meter with an RJ-11 connector at the end as shown in Figure 2. There is a wire
marker approximately 6 inches from the RJ-11 end with “INT MOD ITM3” printed
on it for identifying that the ITM3 option board is installed.
A3 ALPHA Meter
Circuit Board