© 2008 Siemens Energy & Automation, Inc. All Rights Reserved
ACCESS 9340 and 9360 Meters PMCM-9340D-0208
Appendix B—Using the Command Interface 2/2008
EN–216
Setting Up Individual Harmonic Calculations
The meter can perform harmonic magnitude and angle calculations
for each metered value and for each residual value. The harmonic
magnitude for current and voltage can be formatted as either a
percentage of the fundamental (THD), s a percentage of the rms
values (thd), or rms. The harmonic magnitude and angles are stored
in a set of registers: 13,200–14,608. During the time that the meter is
refreshing harmonic data, the meter posts a value of 0 in register
3246. When the set of harmonic registers is updated with new data,
the meter posts a value of 1 in register 3246. The meter can be
configured to hold the values in these registers for up to 60 metering
update cycles once the data processing is complete.
The meter has three operating modes for harmonic data processing:
disabled, magnitude only, and magnitude and angles. Because of the
extra processing time necessary to perform these calculations, the
factory default operating mode is magnitudes only.
To configure the harmonic data processing, write to the registers
described in Table B–4:
Table B–4: Registers for Harmonic Calculations
Reg No. Value Description
3240 0, 1, 2
Harmonic processing;
0 = disabled
1 = magnitudes only enabled
2 = magnitudes and angles enabled
3241 0, 1, 2
Harmonic magnitude formatting for voltage;
0 = % of fundamental (default)
1 = % of rms
2 = rms
3242 0, 1, 2
Harmonic magnitude formatting for current;
0 = % of fundamental (default)
1 = % of rms
2 = rms
3243 10–60 seconds
This register shows the harmonics refresh interval
(default is 30 seconds).
3244 0–60 seconds
This register shows the time remaining before the
next harmonic data update.
3245 0,1
This register indicates whether harmonic data
processing is complete:
0 = processing incomplete
1 = processing complete
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