Product overview
EL34x3
22
Version: 4.4
2.3.3
Effective power measurement
The EL34x3 measures the effective power P according to the following equation
P: Active power
n: Number of samples
u
(t)
: Instantaneous voltage value
i
(t)
: instantaneous current value
Fig. 14: Power s
(t)
curve
In the first step, the power s
(t)
is calculated at each sampling instant:
The mean value over the measuring interval is calculated. Here too, the correct choice of the intervals is
important, as described in section RMS value measurement (the interval can only be changed
simultaneously for U, I and P).
The power frequency is twice that of the corresponding voltages and currents.
2.3.4
Apparent power measurement
In real networks, not all consumers are purely ohmic. Phase shifts occur between current and voltage. This
does not affect the methodology for determining the rms values of voltage and current as described above.
The situation for the effective power is different: Here, the product of effective voltage and effective current is
the apparent power.
The effective power is smaller than the apparent power.
Summary of Contents for EL3413-0000
Page 1: ...Documentation EL34x3 3 phase power measurement terminal 4 4 2019 03 28 Version Date ...
Page 2: ......
Page 6: ...Table of contents EL34x3 6 Version 4 4 ...
Page 47: ...Installation EL34x3 47 Version 4 4 Fig 33 Other installation positions ...
Page 91: ...Commissioning EL34x3 91 Version 4 4 Fig 88 Incorrect driver settings for the Ethernet port ...