Siemens ACCESS 9340 - Thermal Demand; Demand Current; Predicted Demand

© 2008 Siemens Energy & Automation, Inc. All Rights Reserved.
ACCESS 9340 and 9360 Meters PMCM-9340D-0208
Chapter 4—Metering Capabilities 2/2008
EN–48
Thermal Demand
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 4–5 the interval is set to 15 minutes for illustration purposes.
Demand Current
The meter calculates demand current using the thermal demand
method. The default interval is 15 minutes, but you can set the
demand current interval between 1 and 60 minutes in 1-minute
increments.
Predicted Demand
The meter 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 4–6 illustrates how a change in load can affect predicted
demand for the interval.
Figure 4–5: Thermal Demand Example
99%
90%
0%
PLSD110134
The interval is a window of time that moves across the timeline
15-minute
interval
next
15-minute
interval
Time
(minutes)
Last completed
demand interval
Calculation updates at the end of each interval
% of Lead