Measurement Functions 
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pressed, the input signal of the power meter will be calibrated automatically 
to display the best effects of input signals. 
: Advanced configuration options for oscilloscope function. 
  Phase selection, with three options: A, B, C. The default is 
Phase A in the standalone mode. You can switch the three options under three-
phase mode.
 
V-range 100V: 
Adjust voltage range 
I-range 1A: 
Adjust current range 
Timebase: 
Adjust time base range 
U Trig-level
: Voltage trigger setting 
I Trig-level: 
Current trigger setting 
Delay:0.00ms: 
Adjust trigger delay 
 
 Display trigger source edge Settings, parameters are: rising edge, falling 
edge, rising and falling edge, pulse. 
 
7.3 Harmonic measurement 
IT7900 series source can display harmonic parameters in the list or bar chart 
form to make the analysis of test result clear. 
Press     key on the front panel, and the following initial interface of 
harmonic measurement will appear. 
z  Harmonic bar chart screen 
 
 
Description of keys on the harmonic display interface: 
/ : Select the voltage/current harmonic 
: Distortion factor calculation formula. 
%r: displaying harmonics in the form of percentage to the overall voltage 
amplitude of all harmonics. 
%f: displaying harmonics in the form of percentage to the fundamental voltage. 
: Used for save the present waveform data(CSV format), the U disk must 
be insert, otherwise, error information will appear.   
THD: Under single phase mode, display total harmonic distortion of the single 
phase. Under three-phase mode, display total harmonic distortion (THD) factors