Atec Vanguard-ATRT-03-S2 - Manual (Page 2)

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Automatic 3-Phase Transformer Turns-Ratio Tester
The ATRT-03 S2 is Vanguard’s third generation, microprocessor-based, automatic, three
phase, transformer turns-ratio tester. This lightweight and rugged portable unit is
designed for transformer testing at utility power substations.
The ATRT-03 S2 determines the transformer turns-ratio using the IEEE C57.12.90 meas-
urement method. The ATRT-03 S2 outputs an excitation test voltage to the transformer’s pri-
mary windings. The induced secondary voltage is sensed and the transformer turns-ratio is
calculated. The ATRT-03 S2 can measure turns-ratios from 0.8 to 15,000. The transformer
turns-ratio, excitation current, and phase-angle readings are displayed on the large back-
lit LCD. The built-in transformer type detection feature allows the ATRT-03 S2 to detect and
test 130 transformer types defined by ANSI, CEI/IEC and Australian standards.
The ATRT-03 S2 can be used as a stand-alone unit or can be computer-controlled. It can
be operated locally using its alpha-numeric keypad and rotary switch. Information is
displayed on a back-lit LCD screen (64 x 128 dot graphic) that is viewable in both
bright sunlight and low-light levels. Test reports can be printed in the field on the unit’s
built-in 4.5-inch wide thermal printer. The ATRT-03 S2 is capable of storing up to 112
test records and 128 test plans in Flash EEPROM memory. Test records or test plans can
be stored or transferred to and from a PC via the available interfaces (RS-232C port,
USB port, USB Flash drive port).
Transformer Test Voltage
To prevent an accidental wrong test-lead hook-up (e.g., when the operator reverses H and
X leads), the ATRT-03 S2 outputs a low-level test voltage to verify the hook-up condition
before applying the full test voltage to the transformer. Three test voltages (8 Vac, 40 Vac,
100 Vac) allow the ATRT-03 S2 to test CT’s and PT’s, as well as power transformers.
Auto-Detect Transformer Configuration
The ATRT-03 S2 can automatically detect 130 specific vector groups for different trans-
former types defined by ANSI, CEI/IEC, and Australian standards.
User Interface
The ATRT-03 S2 features a back-lit LCD screen (64 x 128 dot graphic) that is viewable
in both bright sunlight and low-light levels. The test results screen displays the trans-
former turns-ratio, excitation current, phase angle, and percentage error. The unit is
controlled via a rugged, 16-key, membrane keypad and a digital rotary switch.
Automatic Three-Phase Turns-
Automate
Transformer Test Plans
The ATRT-03 S2 can store up to 128 transformer test-plans in its Flash EEPROM. A test-plan
is comprised of the transformer nameplate voltages for each tap setting. The calculated
turns-ratio based on the nameplate voltages is compared with the measured turns-ratio. By
recalling a test plan, a transformer can be quickly tested and turns-ratio Pass/Fail reports
can be reviewed. Test plans can be created with the PC software and can be transferred to
the ATRT-03 S2 via the available interfaces (RS-232C port, USB port, USB Flash drive port).
Test Record Storage Capabilities
Up to 112 test records can be stored in the ATRT-03 S2’s Flash EEPROM memory. Each
test record may contain up to 33 turns-ratio, excitation current, phase angle and name
plate voltage readings. Test records can be recalled locally or transferred to a PC via the
available interfaces (RS-232C port, USB port, USB Flash drive port).
USB Flash Drive Interface
A built-in USB Flash drive interface provides a convenient method for transferring test
plans and test records to or from a USB Flash drive. The user can store up to 999 trans-
former test plans on a USB Flash drive. Test plans can be transferred from a PC to a USB
Flash drive, and then a specific test plan on the USB Flash drive can be transferred to
the ATRT-03 S2’s internal Flash memory. Up to 999 test records from the field can be
stored on a USB Flash drive. Test records stored in the ATRT-03 S2’s internal memory
can also be transferred to a USB Flash drive. The supplied PC software can then be used
to view the test records stored on the USB Flash drive.
Computer Interface
In computer-controlled mode, the unit can be controlled via the RS-232C or USB port
using the supplied PC software (Transformer Turns-Ratio Analyzer application provided
with each ATRT-03 S2). This Windows® XP/Vista-based software can be used to run a test
and to store test results on a PC. Test results can also be exported to Microsoft® Excel.
Thermal Printer
A built-in 4.5-inch wide thermal printer prints test results in a 14 point font for easy view-
ing. The printer and paper dispenser are mounted under the front panel for protection.
Transformer Load Tap Changer Control
Transformer tap positions can be changed remotely using the unit’s built-in transformer
load tap changer. This remote-controlled tap changer feature eliminates the need to
manually change a transformer’s step-up and step-down taps.
ATRT-03 S2 Input Power Sources
The ATRT-03 S2 can be powered from a single-phase 100-240 Vac 50/60 Hz power
source. A built-in safety ground detection circuit can detect and display a ground fault
problem with the AC input source.
ATRT-03
ATRT-03 S2 TM
Connections