User's Manual

PG421005A A3 ALPHA Meter/Collector
July 2003 5
The A3 ALPHA meter and the ILC1 option board typically operate independently
of each other. The primary task of the ILC1 option board is to maintain the local
area network (LAN) and read and store billing data from REX meters. The ILC1
option board communicates with the A3 ALPHA meter/collector to read time and
day type information. This information is then propagated through the LAN to the
REX meters. The time base in the A3 ALPHA meter/collector is used as the
system time for the LAN, and the ILC1 option board periodically reads this time
and distributes the time to the LAN.
Billing Date
The billing date (or, the demand reset date) for the A3 ALPHA meter/collector can
be controlled by either of the following:
■ internally by the calendar in the A3 ALPHA meter
■ externally by MAS when the MAS calls the A3 ALPHA meter/collector on the
billing date and issues a demand reset command
Billing dates for REX meters in the LAN are handled by the ILC1 option board.
The ILC1 option board can assign each REX meter to one of thirty billing dates.
Using the billing date information, the ILC1 option board will make certain that the
associated REX meters reset demand on the correct billing date. Before resetting
demand, a REX meter will record a copy of the billing data. This billing data copy
will then be read and stored by the ILC1 option board.
TOU Schedules
If the A3 ALPHA meter/collector is a TOU meter, TOU switch points are controlled
by the A3 ALPHA meter. The ILC1 option board controls TOU switch points for
REX meters in the LAN. Each REX meter can be assigned to one of seven TOU
schedules, where each schedule consists of weekday, weekend, and two special
(that is, holiday) day types. The ILC1 option board broadcasts the TOU schedules
to the REX meters, where they are stored and used to record kWh data in the
correct TOU register. The ILC1 option board reads and stores TOU data from
each REX meter as part of the normal billing read.
Season Changes
Season changes for the A3 ALPHA meter/collector are controlled by the calendar
in the A3 ALPHA meter. Season changes for the REX meters are controlled by
calendars in the ILC1 option board. The ILC1 option board has season change
dates for each of the seven TOU schedules. Using the season change informa-
tion, the ILC1 option board makes certain that the associated REX meter perform
a season change on the correct date. After a season change, the ILC1 option
board will read and store a season change copy of the billing data from associ-
ated REX meters.
Operation of the
A3 ALPHA Meter with
ILC1 Option Board