User's Manual

Operation: CVSO OpenWay Register
CENTRON® OpenWay™ Meter Technical Reference Guide 29
Upon the return of AC power, the register undergoes a procedure similar to the initial
power-up. The meter performs self-diagnostic checks, data is retrieved from non-volatile
memory, and normal operation is resumed. The number of minutes of power outage
maintained while the meter was in carry-over operation, is added to the Time on Battery
register. Since the demand interval is synchronized to the top of the hour, the first demand
interval after a power outage may be shorter than the programmed interval value.
Cold Load Pickup
Normally, when power is restored to the meter after an outage, a new demand interval is
started and demand calculations begin immediately. The meter can be configured to
recognize a demand delay or cold load pickup (CLPU) time. If a CLPU is configured in the
meter, the meter will delay demand calculations for the configured amount of time—0 to
255 minutes in one-minute increments. For example, if a CLPU time of five minutes is
programmed into the meter, a power outage will cause the meter to wait five minutes after
power restoration before resuming demand calculations.
Defining CLPU as zero will cause demand calculations to restart immediately after
any recognized power outage.
Interval Make-up
During power-up processing, the Load Profile component checks if the duration of the
outage exceeds the configured minimum duration time. If it does, then at least one interval
will be tagged with an outage status. The interval that was active when outage occurred is
tagged as a partial interval due to the outage. If the outage ended in the middle of another
interval, then that interval is also tagged as a partial interval due to the outage. If any
intervals occurred in between, then those intervals are tagged as skipped intervals due to the
outage and their data will be all zeroes.
Operating Modes
The OpenWay Register has two operating modes: Normal Mode and Test Mode.
When the meter is placed in Test Mode, it ceases all normal billing functions. The
TEST switch can be used to control the operating mode of the OpenWay Register.
Normal Mode
Normal Mode is the standard mode of operation and the mode in which the meter
automatically starts when energized. Selected quantities are measured and processed in
billing registers. During this mode of operation, billing registers are saved in non-volatile
memory during power outages.
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