GE Power Quality Meter Series, Инструкция по эксплуатации

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GE Power Management PQM Power Quality Meter 6-13
6 SOFTWARE 6.6 POWER ANALYSIS
6
6.6 POWER ANALYSIS 6.6.1 WAVEFORM CAPTURE
Two cycles (64 samples/cycle) of voltage and current waveforms can be captured and displayed on a PC using
PQMPC or third party software. Distorted peaks or notches from SCR switching provides clues for taking cor-
rective action. Waveform capture is also a useful tool when investigating possible wiring problems due to its
ability to display the phase relationship of the various inputs. The waveform capture feature is implemented
into PQMPC as shown below.
Select the
Actual > Power Analysis > Waveform Capture
menu item. PQMPC will open the Waveform Capture
dialog box.
• Check the boxes on the left to display the desired waveforms. The waveform values for the current cursor
line position are displayed to the right of any checked boxes.
• The
Trigger Selected Waveforms
button captures new waveforms from the PQM.
• The
Read Selected Waveforms From Device
button loads and views previously selected waveforms.
• The
Open
button loads and views previously saved waveforms
• The
Save
button saves the captured waveforms to a file
• The
Print
button prints the currently displayed waveforms
• The
Setup
button allows for the setup of capture attributes
6.6.2 HARMONIC ANALYSIS
Non-linear loads such as variable speed drives, computers, and electronic ballasts can cause harmonics which
may lead to problems such as nuisance breaker tripping, telephone interference, transformer, capacitor or
motor overheating. For fault diagnosis such as detecting undersized neutral wiring, need for a harmonic rated
transformer or effectiveness of harmonic filters; details of the harmonic spectrum are useful and available with
the PQM and PQMPC.