7
Ratio: generally select the default value.
Notes to the calibration parameter settings:
The difference between "photoelectric" mode and manual mode is large.
For example: check the three-phase mechanical active energy meter, and the electric energy
constant is 450 r/kW. h and the set number of laps is 2.
When calibrating by use of the photoelectric mode, every time when the energy meter’s black
mark moves a lap, the photoelectric sampler generates a pulse; the error calculation is made at a
time when the instrument receives three times of pulse signals in total.
When using the "manual" mode to calibrate, press the manual switch at a time when the energy
meter’s black mark moves a lap. The error can be calculated at a time when the instrument
receives a pulse signal.
3.2 Harmonic analysis
Function description
1. Perform the 2nd ~ 51st harmonic analysis on the measured signal, and test the total harmonic
distortion rate, odd and even times and each harmonic content.(note: test the 2nd ~ 21st
harmonics according to the national standard)
2. Test and analyze three-phase voltage and current, respectively, show the harmonic content of
each harmonic in the form of corresponding light bar chart, and display the percentage of
corresponding harmonic content accordingly.
Press "3 harmonic" key to enter the "harmonic" state, and after entering the interface, the
interface below displays voltage, current and sorting three options; select voltage and press "F2"
key, choose current and press "F3", select sorting and press "F5", show the each harmonic
content of current or voltage according to the operation, and the biggest harmonic on the scale
line is full scale. If the harmonic is very small, only parts per ten thousand, such as maximum
0.06%, the percentage value of the highest scale is 0.06%, and the subtle harmonic is amplified,
clear at a glance.
The instrument can test a total of 2nd ~ 51st harmonics, and show harmonic spectrum and give
out the percentage content of each harmonic. The 21
st
harmonic is used as an example in the
following to calculate (the 51
st
harmonic is calculated the same as the 21
st
harmonic)
Wherein:
Percentage content of each harmonic - refers to the percentage of the effective value of the 2nd ~
21st harmonic relative to the effective value of fundamental wave, defined as follows:
(of which i = 2, 3, 4 · · · · · · 21; Ui is the effective value of each harmonic, and
U1 is the effective value of fundamental wave.);
