User's Manual

Operation: C1SD, C1ST, and C1SL Versions
CENTRON Meter Technical Reference Guide 5-15
Demand Reset
A demand reset can occur in both Normal and Alternate modes.
A demand reset can occur in two ways:
• Through the optical port using a compatible programming device
• With the standard push-button demand reset switch located on the face of the
meter (see Figure 5.2)
When a demand reset is initiated, the following events occur:
• As an indication of a demand reset, the display flashes all eights for six
seconds.
• The current maximum demand values are added to the corresponding
Cumulative Demand values.
• A self-read is performed (if selected).
• All Maximum Demand values are reset to zero. All corresponding times and
dates of maximum demands are cleared (C1ST and C1SL only).
• The number of demand resets is increased by one.
• The number of in-service days since the last reset is set to zero.
• The time and date of the last reset is updated (C1ST and C1SL only).
• The normal mode display resumes. Exception is when in test mode, the display
resumes with next item in display list.
As a security feature, additional manual demand resets are prevented for 60
seconds following a demand reset.
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.
When a demand reset is performed on a meter programmed for Block Demand, the current
interval becomes the first interval in the next billing period. For Rolling Demand, all previously
completed subintervals are zeroed. The current subinterval becomes the first subinterval in the
next billing period. In Test mode, a demand reset will initialize the demand test interval.