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PA3000 Four-channel, Multi-phase AC/DC Power Analyzer
Efficiency Testing Three Phase Applications
DEMONSTRATION GUIDE
2. Connect the three phase output of the PWM drive to other three channels using
the 3-phase 4-wire configuration as shown in the wiring diagram.
– All three phases are set up in series with the internal shunt and the voltage
is measured across respective phase and neutral.
3. If the motor drive does not have a dedicated neutral cable, create a floating neutral by
connecting all three VLO terminals on channels 2, 3, and 4 together.
4. After making all of the connections, set the PA3000 to the default configuration:
–
Press
.
– Scroll down to
User Configuration and press
.
– Select
Load Default Configuration, and then press
to confirm.
The PA3000 will load the defaults and display a confirmation screen. Press
and then
return to the Main Menu by pressing
.
5. To select the correct wiring configuration within the Main Menu, go to
I
nputs
Wiring
Configuration and select 1 Phase 2 Wire for Group A.
6. Scroll to Group B by pressing the arrow key on the left front panel and select 3 Phase 4 Wire.
NOTE: If desired, both groups can be named for ease of monitoring. Go back one step
and enter the appropriate name using the Group Name option.
7. The PA3000 makes it easy to configure important settings using default modes.
For the PWM motor drive output, from the Main Menu, select
Modes
Select Mode
PWM Motor.
– The PWM Mode will set up the PA3000 to accurately measure the output voltage of a
typical PWM drive that switches at high frequencies. The algorithm applies a proprietary
sensing method to determine the actual fundamental power frequency in real time for all
power calculations so that the calculated power and harmonic data are always accurate
even in dynamic speed conditions.
– The PWM Mode is not required for the input line frequency measurements.
– To enable sum measurements for the three phase output on group B, enable the Sum
Results column by entering the Main Menu and going to
Measurement Configuration
Sum Results Column
Enabled.
Figure 2-2. PWM motor drive efficiency (1 phase in and 3 phase out).
