Schlumberger Sema C1A-1 User Manual
Operation: C1SD, C1ST, and C1SL Versions
5-16
CENTRON Meter Technical Reference Guide
Daylight Savings Time
Daylight Savings Time switch points occur at 2:00
A
.
M
. on the first Sunday in April
and the last Sunday in October. These dates are pre-assigned in the Calendar
Schedule; however, they can be modified by the user. The user can also elect not to
recognize Daylight Savings Time and operate the meter in standard time only.
Schedule; however, they can be modified by the user. The user can also elect not to
recognize Daylight Savings Time and operate the meter in standard time only.
Registers
Current Season Register
All energy and demand registers selected for the active season are considered
current season registers. If a single rate schedule is applicable year-round, then
only current season registers are used.
current season registers. If a single rate schedule is applicable year-round, then
only current season registers are used.
Last Season Registers
Last Season Registers are selected when two or more seasons are used during the
year. For every Current Season Register there is a Last Season Register for the
same quantity. Last Season Registers are designated LS in the programming
software. Last Season Registers can also be selected for display in Normal and
Alternate display modes.
year. For every Current Season Register there is a Last Season Register for the
same quantity. Last Season Registers are designated LS in the programming
software. Last Season Registers can also be selected for display in Normal and
Alternate display modes.
Operation
At the end of a specified season, all Last Season Registers are updated with
Current Season register data. The meter can be programmed to activate an
automatic demand reset at a season change. A season change can be programmed
to occur at midnight at the beginning of the programmed Season Change date or at
the first demand reset following the Season Change date.
Current Season register data. The meter can be programmed to activate an
automatic demand reset at a season change. A season change can be programmed
to occur at midnight at the beginning of the programmed Season Change date or at
the first demand reset following the Season Change date.
Season Change
The following events take place when an automatic demand reset occurs at season
change:
change:
•
The Current Season energy registers are copied directly to the Last Season
energy registers.
energy registers.
•
The Current Season maximum demand registers are copied directly to the Last
Season maximum demand registers and added to the cumulative demand
registers.
Season maximum demand registers and added to the cumulative demand
registers.
•
After the demand reset, the maximum demand registers are reset to zero. Both
the cumulative and the continuous cumulative demand registers are copied to
the Last Season cumulative and continuous cumulative demand registers,
respectively.
the cumulative and the continuous cumulative demand registers are copied to
the Last Season cumulative and continuous cumulative demand registers,
respectively.
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.
directly copied to Last Season registers at season change but no current season
registers are zeroed.