TRT3x Getting Started
M-T03XNN-205-EN
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When generating a true three-phase test voltage, TRT3x generates a true three-phase excitation test
voltage to three transformer primary windings. The induced three-phase voltages across the unloaded
transformer windings are measured and the transformer turns ratio is calculated.
Test voltages of 1 V, 8 V, and 10 V are recommended for current transformers (CT) testing. For testing
distribution or power transformers it is recommended to use the highest test voltage of 100 V or 80 V.
Otherwise a test voltage of 40 V can also be used. Pressing
UP/DOWN
the user selects the value of his/her
choice and then confirms it by pressing
ENTER
.
TRT3x automatically detects if it is connected to a DC power supply. It also automatically detects if the
power supply frequency is 50 Hz or 60 Hz. The frequency of the output voltage is the same as the frequency
of the power supply of TRT3x. In case TRT3x is connected to a DC power supply, the user has to choose
the frequency of the output voltage to be either 50 Hz or 60 Hz.
After the test voltage (and frequency) is selected, the user can select a memory location manually (Test
Reading and Test Record).
SET
is used to scroll between the Test Reading and Test Record options.
Selection of Test Reading or Test Record is performed by using
UP/DOWN
.
Pressing
ENTER
confirms a
selection.
Test Reading can contain, for example, all the test results obtained in one tap changer position of the
transformer. Test Record can contain the results of all tap changer positions, or the complete results
obtained from one transformer.
Note:
Manual selection of record/reading will delete results from the existing memory locations.
Once these parameters are defined, pressing
ENTER
changes the status to the
READY
state.
If one of the values has to be changed, press
STOP
to return to the previous menu.
The flashing green LED indicates TRT3x is now ready to start the test. Press
START
to run a test. During
the test, the red LED glows continuously signaling that the test voltage is applied. Pressing
STOP
(the
CONFIGURATION
menu is displayed) will interrupt (abort) the test. When the test is completed, TRT3x
displays the test results. To scroll between all the results press
ENTER
. Once all the results are viewed, user
can choose whether to test the next tap or to finish the test.
If the AVGD option is selected in the
CONFIGURATION
menu, TRT3x will try to automatically detect a
vector group of the transformer being tested. The user will be asked whether to continue the test with a
detected vector group or to select one of the available vector groups. If for some reason the vector group
cannot be detected, the device will display the
message “Unable to detect vector group” and the test will be
aborted. Once the vector group is detected and confirmed, TRT3x continues with the test. After the test is
finished, TRT3x displays the test results. To scroll between all the results, the user will press
ENTER
. Once
all the results are viewed, user can choose whether to test the next tap or to finish the test.
Figure 3-3:
The
READY
state
before the test
