Pag. 139 di 152
If the data are used for drawing a load profile of Active Demand in kW it is
necessary to:
-
determine the energy readings of each period by calculating the
difference of one period with respect to earlier period (e.g. value at
00,15 hours minus value at 00.00 hours, and so on.
-
transform the value (expressed in 1/10 of kWh) into a kWh value by
dividing the above difference by 10000.
-
multiply the result by 4 (the value is referred to 15 min but it needs to
be referred to 1 hour)
The formula to apply to the 1st cell is therefore : =(D19-D18)/10000*4
By
copying
the 1st cell and
pasting
it into the following cells the formula is
extended to the entire column.
The same operation is applied to the import Reactive Energy, for
determining the Reactive Demand in kvar, by copying and pasting the
formulas in the side columns.
The left column was formatted to show time only by selecting the HOUR
format for cell/column (in order to hide the date indication).
N.B. due to limited space, the example above shows only a portion of
readings out of one day.
Upon graphing the data obtained, the resulting graph will show as below
indicated.
28 May 2005
0
1
2
3
4
5
6
7
0.
15
1.
30
2.
45
4.
00
5.
15
6.
30
7.
45
9.
00
10.
15
11
.3
0
12
.4
5
14.
00
15.
15
16.
30
17.
45
19
.0
0
20
.1
5
21.
30
22.
45
0.
00
P imp kW
Q ind imp kvar
Time
P imp kW Q ind imp kvar
0.15
0,9428
0
0.30
1,0668
0
0.45
0,7984
0
1.00
0,7844
0
1.15
0,7984
0
1.30
0,8324
0
1.45
0,8396
0
2.00
0,7484
0
2.15
0,748
0
2.30
0,906
0,0004
2.45
0,7388
0
3.00
0,7572
0
3.15
0,8044
0
3.30
0,8672
0
3.45
0,776
0
4.00
0,7464
0
4.15
0,7672
0
4.30
0,8404
0
4.45
0,72
0
5.00
0,6828
0
5.15
0,8212
0
5.30
0,8428
0
5.45
0,7332
0
6.00
0,7568
0
6.15
0,7292
0
6.30
0,714
0
6.45
0,6272
0
7.00
0,5948
0
7.15
0,7436
0
7.30
0,7288
0
7.45
0,6184
0
8.00
0,6724
0