24
TRT33A Getting Started
The next step is to enter nameplate voltage values or memory location. To confirm the selection press
ENTER
and proceed to the
READY
state (Figure 5-21).
5.2.3.2 Measurement on Three-phase Autotransformers
Press
UP/DOWN
to choose a configuration in the CONFIG field of the
AUTOTRANSFORMER
menu. To
confirm your selection, press
ENTER
.
Available autotransformer vector groups in the
AUTOTRANSFORMER
menu are displayed in Table 7.
After pressing
ENTER
, cursor will automatically go to the phase displacement position.
Displacement field is not required. If you do not enter a value in this field, TRT33A device will continue
with the measurement. Available options for phase displacement in this menu are listed in Table 8.
If one of these values has to be changed, press
STOP
to return to the previous menu or press
UP/DOWN
to navigate to the BACK option and press
ENTER
to confirm.
Table 7:
Available vector group configurations
Config
PH Displacement
Comment
Da
Displayed
delta winding
Ya
Displayed
star winding
YNa
Displayed
star winding with neutral point
Za
Displayed
zigzag
ZNa
Displayed
zigzag with neutral point
AVGD
Hidden
automatic vector group detection
TRUE 3~ TEST
Hidden
only true three-phase test
SINGLE
Hidden
single phase autotransformer
Table 8:
PH displacement
Configuration
PH displacement
Ya, YNa
0-4-8
Da, Za, ZNa
0-1-2,...11
When you select the AVGD option, the TRT33A will automatically detect vector group of the
autotransformer under test.
You can also select
TRUE 3~ TEST
in
AUTOTRANSFORMER
menu. The TRT33A will perform the test
by applying the true three-phase test voltage.
After selecting the vector group and other parameters for the autotransformer, press
ENTER
to confirm
selection. The menu with the name plate voltage values is displayed (if the calculation of the ratio
deviation option is enabled). Enter the nameplate voltages for autotransformer and press
ENTER
to
confirm the selection. Once the memory location, name plate voltages, and the test voltage are defined,
press
ENTER
to go to the
READY
state (Figure 5-21). The flashing green LED indicates that TRT33A is
now ready to start the test. Press
START
to run a test. The red LED flashes continuously during the test.
Press
STOP
, if you want to abort the test.
Note
:
If one of these values has to be changed, press
STOP
to return to the previous menu.
Figure 5-32:
Choosing vector group in
AUTOTRANSFORMER
menu
