User's Manual
ANSI Electric Meter v3.1 User’s Guide 63
Self-Reads
The meter can be programmed to perform an automatic periodic reading of
measurement data, along with a timestamp. This is called a self-read. The time of
day that a self-read occurs is configurable. A self-read can be set to repeat daily,
weekly, monthly, or yearly.
If the meter is powered-down at the time a self-read is scheduled to occur, the self-
read will be recorded the next time the meter is powered-up, with a timestamp of
when the actual reading occurred.
The meter stores one copy of the most recent self-read data and up to 23 sets of
previous self-reads. Whenever a new self-read occurs, the oldest stored self-read data
set is overwritten if 24 sets are already stored. A snapshot of the following data is
recorded during a self-read:
Total and tariff-specific active and reactive energy values
Time, date, and season when data was captured
Total power outage minutes and counts that occurred since the meter went
into operation (or since all registers were reset to zero)
All demand metering data, if configured
One-Time Reads
You can also program the meter to perform a One-time-read. A One-time-read
returns the same set of data as described for a Self-read in the previous section. The
only difference between a One-time-read and a Self-read is the scheduling. One-
time-reads do not occur multiple times in a scheduled pattern as Self-reads do. Each
One-time-read is programmed to occur at a specific date and time, and occurs only
once. You can schedule up to 3 separate One-time-reads in the meter at once.
If the meter is powered-down at the time a One-time-read is scheduled to occur, the
One-time-read will be recorded the next time the meter is powered-up, with a
timestamp of when the actual reading occurred.
The meter stores up to 2 sets of One-time-reads. Whenever a new One-time-read
occurs, the oldest stored One-time-read data set is overwritten if 2 sets are already
stored.
Daily Energy Consumption
Each day at UTC midnight the meter stores the total active and reactive energy
consumption amounts for the previous 24 hours.
Time-of-Use (TOU) Tariffs
Time-of-Use (TOU) is the term used to describe the partitioning of energy usage into
different registers based on a schedule. The meter supports four such registers,
called tariffs (T1, T2, T3, and T4). The tariffs are selected for different time periods
within a day (midnight to midnight). The time at which a tariff is changed is called a
tier switch. Each 24-hour set of tier switches is called a day schedule. There may be
different day schedules for weekdays, Saturday, Sunday, and holidays. Each year is
identical with regard to season changes, holidays, and daylight saving time
scheduling. This is called a perpetual calendar implementation. All of the measured