Operation: CP1SD/T/L Version
52
CENTRON® Polyphase Meter Technical Reference Guide
Rate Annunciators and Active Rate Indicators
Rate annunciators are available with each demand and energy register. An A, B, C, or D will
be displayed on the far right side of the LCD to indicate the rate period for each quantity
being displayed. The rate annunciator that may be displayed for the Total Rate is
T
.
T
If the rate annunciator is flashing while a demand or energy value is displayed, the
annunciator indicates that it is the current rate in effect. This gives a quick indication that
the register is programmed with the correct TOU schedule and that it is currently set to the
correct time.
Season Change
At the end of a specified season, all last season registers are updated with current season
register data. The meter can be programmed to either delay the season change until a
demand reset occurs, to activate an automatic demand reset at season change, or to change
the season without performing a demand reset. A season change occurs at midnight at the
end of the programmed season change date or at the first demand reset following the season
change date, depending on how the meter has been programmed. Some utilities program the
season change to occur at the first demand reset following the season change date to make
season changes concurrent with the meter reading cycles.
The following events take place when an automatic demand reset occurs at a season change:
1
The current season energy registers are copied directly to the last season energy
registers.
2
The current season maximum demand registers are copied directly to the last season
maximum demand registers, and
T
rate is added to the cumulative demand register.
T
3
After the demand reset, the maximum demand registers are reset to zero, and the
T
rate
cumulative demand register is copied to the last season cumulative demand register.
T
If there is no demand reset at season change, all current season registers are directly copied
to last season registers at season change, but no current season registers are zeroed.
Battery Carryover
When the meter recognizes a power outage, it begins battery carryover operations. Billing
data is transferred to non-volatile memory at this time, and all circuits, except the RAM and
timekeeping circuit, are de-energized. The timekeeping circuitry, powered by the lithium
battery, keeps time while the meter is in battery carryover mode.
Upon restoration of AC power, all self-diagnostics are completed, and data is retrieved from
non-volatile memory. The real time is retrieved from the real time clock. The elapsed time
of the outage is also added to the stored value for the time spent on battery.
