User's Manual

Operation: C1SD, C1ST, and C1SL Versions
CENTRON Meter Technical Reference Guide 5-15
Time-of-Use
TOU Schedules
The Time-of-Use capability is available on the C1ST and C1SL personality modules.
It requires additional circuitry to store TOU schedule information and a battery for
time-keeping purposes during power outages. Schedule information is
programmed on a PC using the PC PRO+ software packages.
When using TOU functions on a meter, energy and demand registration are
segregated into time blocks during the day. Each time block can be one of four rate
periods. In addition to these four rate periods, a total rate is also available.
Calendar Schedule
The calendar schedule contains all daily and yearly information necessary to
perform TOU metering. This schedule contains rate schedules, daily schedules,
seasons, holidays, and daylight savings time dates. For information on the entry of
these parameters into PC-PRO+, refer to the PC-PRO+ documentation.
Rate Schedules
Four independent rates are available for TOU registration-designated A, B, C, and
D. Only one of these rates can be active at a time. The Total register is always
active, regardless of the active rate period. The currently active rate is indicated by
a flashing rate-specific annunciator.
Daily Schedules
Up to four daily schedules are available. Each schedule defines the beginning and
ending time of each of the four available rate periods (A, B, C, and D). Up to 32
switch points per rate may be specified for each daily schedule.
Weekdays, Saturday, Sunday, and holidays can be assigned to one of the four daily
schedules. Therefore, one to four daily schedules may be used in any combination
with the days of the week.
Seasonal Schedules
A season is a period of continuous days during the year when a particular rate
schedule is in effect. The year can be divided into a maximum of eight seasons. If
multiple seasons are not used, the TOU schedule contains one year-round season.
The Daily Schedules can be defined differently for each season. Up to eight Season
Change dates are specified for each year in the Calendar Schedule.
Season changes occur at midnight of the Season Change date (where midnight
corresponds to 00:00 hours) or can be programmed to occur at the first demand
reset following the Programmed Season Change date.
Holiday Schedules
Up to twenty-two holidays can be designated per year in the Calendar schedule.
One of the four Daily schedules is assigned to each of the Holidays in the Calendar
Schedule.