VAMP 52 - THD and harmonics; 4.2. RMS values; RMS currents; RMS voltages

4.2 RMS values 4 Measurement functions Technical description
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Voltage input U
The usage of voltage inputs depends on the configuration
parameter voltage measurement mode. For example, U is the
zero sequence voltage input U
0
if the mode “U
0
” is selected.
Measuring range 0 – 160 V
Inaccuracy 0.5 % or 0.3 V
The specified frequency range is 45 Hz – 65 Hz.
Residual current input I
0
Measuring range 0 – 10 xI
n
Inaccuracy I  1.5 xI
n
0.3 % of value or 0.2 % of I
n
I > 1.5 xI
n
3 % of value
The specified frequency range is 45 Hz – 65 Hz.
The rated input I
n
is 5A, 1 A or 0.2 A. It is specified in the order
code of the relay.
Frequency
Measuring range 16 Hz – 75 Hz
Inaccuracy 10 mHz
The frequency is measured from current signals.
THD and harmonics
Inaccuracy I, U > 0.1 PU 2 % units
Update rate Once a second
The specified frequency range is 45 Hz – 65 Hz.
4.2. RMS values
RMS currents
The device calculates the RMS value of each phase current. The
minimum and the maximum of RMS values are recorded and
stored (see chapter 4.5).
2
15
2
2
2
1
...
fffrms
IIII 
RMS voltages
The device calculates the RMS value of each voltage input. The
minimum and the maximum of RMS values are reco
rded and
stored (see chapter 4.5).
2
15
2
2
2
1
...
fffrms
UUUU 