Vanguard ATRT-01 S2 - Manual (Page 6)

ATRT-01 S2, ATRT-01B S2, AND ATRT-01D S2 USER’S MANUAL REV 2
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1.0 INTRODUCTION
1.1 General Description and Features
The ATRT-01 S2 is Vanguard’s third-generation micro-processor-based, single-phase, automatic,
transformer-turns-ratio tester. This portable test equipment is offered in three models: the
ATRT-01 S2, ATRT-01B S2, and ATRT-01D S2. The ATRT-01 S2 is ac-line powered; the ATRT-01B
S2 is ac-line or rechargeable-battery powered, and the ATRT-01D S2 is powered by six D-cells.
The ATRT-01 S2 determines the transformer turns-ratio using the IEEE C57.12.90 measurement
method. The transformer turns-ratio is determined by precisely measuring the voltages across
the unloaded transformer windings. The ATRT-01 S2’s measuring circuitry self calibrates before
each measurement to ensure turns-ratio accuracy.
The ATRT-01 S2 measures turns-ratios ranging from 0.800 to 15,000 and can be used to test
voltage regulators, power transformers, current transformers (CT), and Potential Transformers
(PT). The ATRT-01 S2 also measures and displays transformer-winding excitation current, and
winding polarity. Test results are displayed on a back-lit LCD screen (4 lines by 20 characters).
In addition to measuring a transformer’s turns-ratio, nameplate voltages can also be entered
via the keypad, and the ATRT-01 S2 will then display the turns-ratio error as a percentage. This
convenient feature eliminates any user-calculation error when testing transformers.
If a 3-phase transformer is being tested, the ATRT-01 S2 will also provide connection
information (H and X test probes to transformer bushings) for phases A, B, and C tests. Three-
phase test results (turns-ratio, excitation current, winding polarity, and percentage error) are
displayed on the LCD screen at the end of each test.
User Interface
The ATRT-01 S2 features a back-lit LCD screen (4 lines by 20 characters) that is viewable in both
bright sunlight and low-light levels. Displayed test results include turns-ratio, winding polarity,
excitation current, and percentage error calculation.
The ATRT-01 S2’s rugged, 16-key membrane keypad is used to select a test and enter the
nameplate voltages for turns-ratio percentage error calculation.
Computer Interface
The ATRT-01 S2, ATRT-01B S2 and the ATRT-01D S2 can be used with a PC via the RS-232C
interface. Windows® XP/Vista-based software is provided with each unit and can be used to
test transformers and to store the test results on the computer. The test results can be
retrieved later, in the office for example, for analysis and for printing on an office printer. The
test results can also be exported in text or Microsoft® Excel format, thus allowing the results to
be used with other PC applications.
The included PC software can also be used to create test plans for specific transformers. A test
plan is comprised of the transformer nameplate voltages for each tap setting. Computed turns-
ratio is based on the nameplate voltages which can be compared to the measured ratio to
derive percentage error.