4
IM 701450-61E
1
Overview of the Power Analysis Function
Correcting (Deskewing) the Difference in the Transfer Time of Analyzed Signals
To correctly measure the analysis parameters (power analysis parameters) such as
power, impedance, power factor, watt hour, and ampere hour from the voltage and
current under analysis, the voltage and current signals must be applied to the signal
input terminals of the DL7400 with no difference in the transfer time. However,
difference in the transfer time may occur between signals depending on the probe that is
being used. When the probe* and deskew correction signal source are connected, the
DL7400 can correct (deskew) the difference in the transfer time of the signals
automatically or manually and measure the power analysis parameters.
*
It is recommended that YOKOGAWA products listed below be used to execute deskew and
measure the power analysis parameters.
Deskew correction signal source
Model 701935
Passive probe
Model 700988
Differential probe
Model 700924 or 701921
Current probe
Model 700937
Automated Measurement and Statistical Processing of Power Analysis Parameters
As with the standard measurement parameters (waveform parameters), the following
power analysis parameters (waveform parameters) can be measured automatically on
the displayed waveform (within the display record length).
Voltage
Amplitude UP-P, maximum value U+pk, minimum value U-pk, DC
component Udc, rms value Urms, AC component Uac, rectified mean
value calibrated to the rms value Umn, and rectified mean value Urmn
Current
Amplitude IP-P, maximum value I+pk, minimum value I-pk, DC
component Idc, rms value Irms, AC component Iac, rectified mean
value calibrated to the rms value Imn, and rectified mean value Irmn
Power
Apparent power S, active power P, and reactive power Q
Power factor
Power factor
λ
of the circuit under measurement
Impedance
Impedance Z of the circuit under measurement
Watt hour
Sum of positive and negative watt hours Wp, sum of positive watt
hours Wp+, and sum of negative watt hours Wp-
Ampere hour
Sum of positive and negative ampere hours q, sum of positive ampere
hours q+, and sum of negative ampere hours q-
Heat energy
Joule integral I
2
t
Automated Measurement of Power Analysis Parameters on Dual Areas
As with the standard measurement parameters, you can specify two areas and perform
automated measurement of power analysis parameters on each area. For details on the
function and procedural explanations, see section 10.8 in the
DL7440/DL7480 User’s
Manual IM701450-01E
.
Statistical Processing
As with the standard measurement parameters, you can perform statistical processing
on the measured values of power analysis parameters. Normal statistical processing,
statistical processing per cycle, and statistical processing of history data are available.
For details on the function and procedural explanations, see section 10.7 in the
DL7440/
DL7480 User’s Manual
.
