Siemens SICAM Q100 - Load-Profile Determination

5 Energy Management
5.1 Load-Profile Determination
80 SICAM Q100, 7KG95xx, Device Manual
E50417-H1040-C522-A4, Edition 03.2018
5.1 Load-Profile Determination
5.1.1 General
The load profile reflects the history of the electric power and documents the distribution of power fluctuations
and peaks. The load profile is determined on the basis of subperiods of 10/12 cycles (50 Hz/60 Hz).
SICAM Q100 supports 2 methods of load-profile determination: the Fixed Block method and the Rolling
Block method.
The load profile is stored in the ring buffer of the device and provided at the communication interfaces (see
chapter 8.3.5.1 and System manual). In addition, it can be output as CSV file.
The load profile can be recorded in synchronized or non-synchronized form. The synchronization is made
by external or internal triggers.
The following diagram shows a 45-min measuring period which consists of 3 subperiods of 15 min each.
The measured and calculated load-profile data are stored in the ring buffer at the end of each subperiod. After
3 subperiods, the average power value of the measuring period is calculated from the 3 load-profile data of the
subperiods. The values (cumulative values and averages) can be retrieved at any time within a subperiod via
the communication.
Figure 5-1 Power history of a measuring period consisting of three 15-min subperiods
10/12 10/12 10/12
15 min
30 min 45 min
Subperiod (a)
Subperiod (b)
P
t
Mean value generation
subperiod (a)
Sampled value
Mean value generation
subperiod (b)
10/12 10/12 10/12
System cycle
System cycle
Start
0 min
Time of detection/Storage
of load profile data
Instantaneous
sampling point
Instantaneous cumulative
average power at the
sampling point
Subperiod (c)
10/12
Measured
power
Calculation of average
power about the
measuring period
Measuring period
10/12
System cycle
Mean value about
the subperiod (a)