Filter
Top Products
Chapter 4—Metering Capabilities 63230-300-212
Demand Readings April 2001
© 2001 Schneider Electric All Rights Reserved
60
The thermal demand method calculates the demand based on a thermal
response, which mimics thermal demand meters. The demand calculation
updates at the end of each interval. You select the demand interval from 1 to
60 minutes (in 1-minute increments). In Figure 4–4 the interval is set to 15
minutes for illustration purposes.
Figure 4–4: Thermal Demand Example
The circuit monitor calculates predicted demand for the end of the present
interval for kW, kVAR, and kVA demand. This prediction takes into account
the energy consumption thus far within the present (partial) interval and the
present rate of consumption. The prediction is updated every second.
Figure 4–5 illustrates how a change in load can affect predicted demand for
the interval.
Figure 4–5: Predicted Demand Example
Thermal Demand
15-minute
interval
next
15-minute
interval
Time
(minutes)
Calculation updates at the end of each interval
The interval is a window of time that moves across the timeline.
Last completed
demand interval
99%
90%
% of Load
0%
Predicted Demand
Predicted demand is updated every second.
15-minute interval
Time
Beginning
of interval
Demand for
last completed
interval
Predicted demand if load is
added during interval,
predicted demand increases
to reflect increased demand
Predicted demand if no load added
Partial Interval
Demand
1:00 1:06 1:15
Change in Load