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Measurements
Related Topics
• Meter resets
Sliding window demand
To calculate demand values, your meter uses the sliding window averaging (or
rolling interval) method which divides the demand interval into a set number of
subintervals of specified duration.
The demand is measured based on the average load level over the most recent
set of subintervals. Sliding window demand also provides predicted demand
values.
Examples of sliding window demand
This example shows two different ways of configuring a 15-minute demand
interval:
• Single interval (also called block or timed block): the 15-minute demand
interval is defined as a single subinterval with a duration of 15 minutes.
• Sliding window (also called rolling block): the 15-minute demand interval is
defined as three subintervals with a duration of 5 minutes each. This method
offers better response time than a single interval.
Single interval (block)
1 5 30 45
Demand value is
the average for the
last completed
interval
Time
(min)
Calculation updates at
the end of the interval
15-minute interval 15-minute interval 15-min
Sliding window (rolling block)
1 5
5 4 0 3 20 35 40 25
Demand value is
the average for
the last completed
interval
Time
(min)
Calculation updates at the end
of the subinterval (5 minutes)
15-minute interval
Incremental energy
Incremental energy allows you to define a start time, end time, and the time
interval (increments) for incremental energy accumulation.
At the end of each interval, the energy accumulated during that period is stored.
By default, the meter only records the previous interval’s incremental energy and
the instantaneous energy accumulations in the active interval.
The first interval of incremental energy accumulation begins at the specified start
time. Incremental energy ends at the specified end time, which may result in a
truncated interval if the interval duration does not divide evenly into the overall
incremental energy duration. For example, an interval duration of three hours with
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