34 Rockwell Automation Publication 1412-UM001D-EN-P - September 2012
Chapter 3 Display Modes
The signs are only available in harmonic power measurement.
The Power and Direction Flow Analysis
example shows a power harmonic
display with the 3rd harmonic highlighted by the cursor. This harmonic is
generated by the load.
Harmonic Analysis in Expert Mode
Press the Up Cursor button to select -.+ and then either the V or A variable
function button V or A.
This is an example of a typical display.
• First column: The harmonics inducing a negative sequence are displayed.
• Second column: Those inducing a zero sequence (triplens added into the
neutral) are displayed.
• Third column: Those inducing a positive sequence are displayed.
Harmonic contest is useful to evaluate the influence of harmonics causing heating
of the neutral or on rotating machines can be analyzed.
By convention, positive harmonics are from supply to load, and negative
harmonics are from load to supply.
07/25/02
02
05
08
11
14
17
20
23
03
06
09
12
15
18
21
24
04
07
10
13
16
19
22
25
59.98Hz 10:26
100
%
.+
3L
L1
L2
L3
7.3
%
0
15.5
%
4.8
%
V A
