Vanguard Instruments Company ATRT-03 User manual

ATRT-03, ATRT-03A, and ATRT-03B
THREE-PHASE TRANSFORMER TURNS-RATIO METERS
USER’S MANUAL
Vanguard Instruments Company, Inc.
1520 S. Hellman Ave.
Ontario, California 91761, USA
TEL: [phone]
FAX: [phone]
August 2010
Revision 7

ATRT-03, ATRT-03A, AND ATRT-03B USER’S MANUAL REV 7
i
SAFETY SUMMARY
This manual applies to the ATRT-03, ATRT-03A, and ATRT-03B current transformer turns-ratio
meters. The operating procedures are virtually the same for all three models, and any
differences are clearly described where applicable.
FOLLOW EXACT OPERATING PROCEDURES
Any deviation from procedures described in this User’s Manual may create one or more safety
hazards, damage the ATRT-03/03A/03B, damage the test transformer, or cause errors in the
test results. Vanguard Instruments Company, Inc. assumes no liability for unsafe or improper
use of the ATRT-03/03A/03B.
SAFETY WARNINGS AND CAUTIONS
The ATRT-03/03A/03B shall be used only by trained operators. All transformers under test shall
be off-line and fully isolated. Always ground the ATRT-03/03A/03B to a substation ground
before connecting the test cables to a transformer. Do not perform test procedures or service
unless another person is also present who is capable of rendering aid and resuscitation.
DO NOT MODIFY TEST EQUIPMENT
To avoid the risk of introducing additional or unknown hazards, do not install substitute parts or
perform any unauthorized modification to any ATRT-03/03A/03B test unit. To ensure that all
designed safety features are maintained, it is highly recommended that repairs be performed
only by Vanguard Instruments Company factory personnel or by an authorized repair service
provider. Unauthorized modifications can cause safety hazards and will void the manufacturer’s
warranty.
WARNING
Do not remove test leads during a test. Failure to heed this warning can result in electrical
shock to personnel and damage to the equipment.

REV 7 ATRT-03, ATRT-03A, AND ATRT-03B USER’S MANUAL
ii
TABLE OF CONTENTS
CONVENTIONS USED IN THIS DOCUMENT ..................................................................................... 1
1.0 INTRODUCTION.................................................................................................................... 2
1.1 General Description and Features ................................................................................... 2
1.2 Technical Specifications ................................................................................................... 4
1.2.1. ATRT-03 Technical Specifications............................................................................. 4
1.2.2. ATRT-03A Technical Specifications........................................................................... 5
1.2.3. ATRT-03B Technical Specifications........................................................................... 6
1.3 Controls and Indicators.................................................................................................... 7
2.0 PRE-TEST SETUP ................................................................................................................. 13
2.1 ATRT-03 and ATRT-03B Operating Voltages .................................................................. 13
2.2 ATRT-03A Operating Voltages ....................................................................................... 13
2.3 LCD Screen Contrast Control.......................................................................................... 13
2.4 Printer Paper Control (ATRT-03 and ATRT-03A Only).................................................... 14
2.5 Printer Paper (ATRT-03 and ATRT-03A Only)................................................................. 14
3.0 OPERATING PROCEDURES ................................................................................................. 15
3.1 Connection Diagrams..................................................................................................... 15
3.1.1. Typical Front Panel Connections.................................................................................... 15
3.1.2. Typical Connections to a Delta-Wye Transformer......................................................... 16
3.2 Setting the Test Voltage................................................................................................. 24
3.3 Setting the Date and Time ............................................................................................. 26
3.4 Enabling the Computer Interface .................................................................................. 27
3.5 Using the Turns Ratio Calculator ................................................................................... 28
3.6 Performing Tests............................................................................................................ 30
3.6.1. Entering Test Record Header Information ............................................................. 30
3.6.2. Testing a Single Phase Transformer ....................................................................... 33
3.6.3. Performing a Three-Phase Test (Y-dT Example)..................................................... 40
3.6.4. Performing a Special Transformer Test.................................................................. 47
3.6.5. Performing a Quick Test ......................................................................................... 53
3.6.6. Testing a Three Phase Transformer Using Auto Detect Mode .............................. 56
3.7.1. Restoring a Test Record From Flash EEPROM........................................................ 59
3.7.2. Reviewing a Test Record........................................................................................ 62
3.7.3. Printing or Viewing the Test Record Directory....................................................... 64
3.7.4. Erasing Test Records from the Flash EEPROM ....................................................... 67
3.8 Working With Test Plans................................................................................................ 69
3.8.1. Performing a Test Using a Transformer Test Plan.................................................. 69
3.8.2. Unloading a Test Plan From the Working Memory................................................ 75
3.8.3. Printing or Viewing the Test Plan Directory ........................................................... 76
3.8.4. Printing a Test Plan (ATRT-03 and ATRT-03A Only)................................................ 78
4.0 DIAGNOSTICS, VERIFICATION, AND TROUBLESHOOTING ................................................. 81
4.1 Performing an H and X Cable Diagnostic Test ............................................................... 81
4.2 Performing a Verification Test ....................................................................................... 82

ATRT-03, ATRT-03A, AND ATRT-03B USER’S MANUAL REV 7
iii
APPENDIX A – TRANSFORMER VECTOR GROUP CODES ............................................................... 84
APPENDIX B – Common ANSI Transformer Descriptions ............................................................. 85
APPENDIX C – CEI/IEC 60076-1 Transformer Descriptions ........................................................... 93
APPENDIX D – Australian Std.2374 Transformer Descriptions................................................... 100

REV 7 ATRT-03, ATRT-03A, AND ATRT-03B USER’S MANUAL
iv
LIST OF TABLES
Table 1. ATRT-03 Technical Specifications...................................................................................... 4
Table 2. ATRT-03A Technical Specifications ................................................................................... 5
Table 3. ATRT-03B Technical Specifications.................................................................................... 6
Table 4. Functional Descriptions of ATRT-03 Controls and Indicators ........................................... 8
Table 5. Functional Descriptions of ATRT-03A Controls and Indicators ....................................... 10
Table 6. Functional Descriptions of ATRT-03B Controls and Indicators ....................................... 12
Table 7. Voltage Selection Jumper Settings.................................................................................. 13
Table 8. Descriptions of Single Phase Test Results Elements (Column Format) .......................... 38
Table 9. Descriptions of Single Phase Test Results Elements (Detailed Format) ......................... 39
Table 10. Descriptions of Dyn1 Test Results Elements (Column Format) .................................... 44
Table 11. Descriptions of Dyn1 Test Results Elements (Detailed Format) ................................... 46
LIST OF FIGURES
Figure 1. ATRT-03 Controls and Indicators ..................................................................................... 7
Figure 2. ATRT-03A Controls and Indicators ................................................................................... 9
Figure 3. ATRT-03B Controls and Indicators ................................................................................. 11
Figure 4. Voltage Selection Jumper Location and Settings........................................................... 13
Figure 5. Typical Front Panel Cable Connections.......................................................................... 15
Figure 6. Typical H & X Cable Connections to a Delta-Wye Transformer..................................... 16
Figure 7. Typical Connections to a Single Phase Transformer...................................................... 17
Figure 8. Typical Connections to a Single Phase Auto Transformer ............................................. 17
Figure 9. Typical Connections to a Type A Voltage Regulator ...................................................... 18
Figure 10. Typical Connections to a Type B Voltage Regulator .................................................... 18
Figure 11. Typical Connections to a Donut Type (un-mounted) Current Transformer (CT)......... 19
Figure 12. Typical Connections to a Multi-Tap Current Transformer........................................... 20
Figure 13. Typical Connections to a Bushing Mount CT on a Single Phase Transformer ............. 21
Figure 14. Typical Connections to Bushing Mount CT's on Delta Transformer............................ 22
Figure 15. Typical Connections to Bushing Mount CT's on Wye Transformer ............................. 23
Figure 16. Single Phase Test Results Printout - Column Format .................................................. 38
Figure 17. Single Phase Test Results Printout - Detailed Format ................................................. 39
Figure 18. Y to Delta Test Results Printout - Column Format....................................................... 44
Figure 19. Y to Delta Test Results Printout - Detailed Format...................................................... 45
Figure 20. Special Dy11 Transformer Test Printout...................................................................... 52
Figure 21. Typical Test Record Directory Printout........................................................................ 66
Figure 22. Test Plan Test Results Printout .................................................................................... 74
Figure 23. Sample Test Plan Printout............................................................................................ 80

ATRT-03, ATRT-03A, AND ATRT-03B USER’S MANUAL REV 2
1
CONVENTIONS USED IN THIS DOCUMENT
This document uses the following conventions:
•The general term “ATRT” is used in this manual to refer to any of the ATRT-03 models
(ATRT-03, ATRT-03A, and ATRT-03B).
•A key, switch, or knob on the ATRT is indicated as [KEY], [SWITCH], [KNOB].
•Menu names are referenced as “MENU NAME”
•ATRT LCD screen output is shown as:
•When instructions are provided, the menu item that should be selected is shown in bold
(option 3 should be selected):
•Warning messages are indicated as:
WARNING
Warning message
•Important notes are indicated as:
NOTE
Note details
1.OPTION 1
2.OPTION 2
3.OPTION 3
4.OPTION 4
1.OPTION 1
2.OPTION 2
3.OPTION 3
4.OPTION 4

REV 2 ATRT-03, ATRT-03A, AND ATRT-03B USER’S MANUAL
2
1.0 INTRODUCTION
1.1 General Description and Features
The ATRT-03 line is Vanguard’s second generation family of microprocessor-based, automatic,
three phase, transformer turns-ratio testers. The ATRT-03 line consists of the following three
models:
•The ATRT-03 is a line-powered, 120/240 Vac (selectable), 50/60 Hz turns-ratio tester
featuring a built-in thermal printer.
•The ATRT-03A can be powered either by an internal rechargeable lead acid battery, by
90-240 Vac, by 110-240 Vdc, or by a 12 Vdc external source. The internal battery
provides 3 hours of operational time. The ATRT-03A also features a built-in thermal
printer.
•The ATRT-03B is a line-powered, 120/240 Vac (selectable), 50/60 Hz turns-ratio tester
without a built-in thermal printer.
The general term “ATRT-03” or “ATRT” is used in this manual to refer to any of the ATRT-03
models. Any differences are clearly described where applicable.
The ATRT-03 determines the transformer turns-ratio using the IEEE C57.12.90 measurement
method. The transformer turns-ratio (ranging from 0.8 to 15,000) is determined by precisely
measuring the voltages across the unloaded transformer windings. To ensure accuracy, the
ATRT-03’s measuring circuitry self-calibrates before each measurement. It requires neither
adjustment nor temperature compensation. The ATRT-03’s turns-ratio measurement accuracy
is 0.1% or better.
The ATRT-03 can perform a specific test for each transformer type (such as single phase, delta
to Y, Y to delta, delta to delta, or Y to Y) without the need to switch test hookup cables. Also,
the unit’s automatic transformer phase detection feature can detect different transformer
vector diagrams. The ATRT-03 can automatically detect and test 67 transformer types defined
by ANSI, CEI/IEC and Australian standards.
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 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 to test CT’s and PT’s, as well as power transformers.
User Interface
The ATRT-03 features a back-lit LCD screen (20 characters by 4 lines) that is viewable in both
bright sunlight and low-light levels. The test results screen displays the transformer turns-ratio,
excitation current, and turns-ratio accuracy. The unit is controlled via a rugged, 16-key,
membrane keypad.

ATRT-03, ATRT-03A, AND ATRT-03B USER’S MANUAL REV 2
3
Transformer Test Plans
The ATRT-03 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 included PC software and can be transferred to
the ATRT-03 via the RS-232C interface.
Internal Test Record Storage
Up to 200 test records can be stored in the ATRT-03’s Flash EEPROM memory. Each test record
may contain up to 99 turns-ratio, excitation current, phase angle, and nameplate voltage
readings. Test records can be recalled locally or transferred to a PC via the RS-232C interface.
Computer Interface
The ATRT-03 can be computer-controlled via the RS-232C interface using the supplied PC
software. The 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.
Transformer Load Tap Changer Control
An optional Tap-Changer Remote Control Box can be used to remotely change transformer
taps. This remote-controlled tap-changer box eliminates the need to manually change the
transformer’s step-up and step-down taps.
Built-in Thermal Printer (ATRT-03 and ATRT-03A only)
A built-in 4.5-inch wide thermal printer prints test results in a 14 point font for easy viewing.
The printer and paper dispenser are mounted under the front panel for protection.

REV 2 ATRT-03, ATRT-03A, AND ATRT-03B USER’S MANUAL
4
1.2 Technical Specifications
1.2.1. ATRT-03 Technical Specifications
Table 1. ATRT-03 Technical Specifications
TYPE Portable, lightweight, automatic, three-phase transformer turns-ratio meter
PHYSICAL SPECIFICATIONS 17”W x 7”H x 13”D (43.2cm x 17.8 cm x 33.0 cm); Weight: 14 lbs (6.4 kg)
INPUT POWER 3 amps, 110 – 120 Vac or 220 – 240 Vac (selectable), 50/60 Hz
MEASUREMENT METHOD ANSI/IEEE C57.12.90
RATIO-MEASURING RANGE 0.8 – 15,000 (5-digit resolution)
TURNS-RATIO ACCURACY 0.8 – 1999: ±0.1%, 2,000 – 3,999: ±0.25%, 4,000 – 15,000: ±1% @ 8 Vac
0.8 – 1999: ±0.1%, 2,000 – 3,999: ±0.20%, 4,000 – 15,000: ±1% @ 40 Vac
0.8 – 1999: ±0.1%, 2,000 – 3,999: ±0.15%, 4,000 – 15,000: ±1% @ 100 Vac
ADJUSTMENT None required
TEST VOLTAGES 8 Vac @ 1 amp, 40 Vac @ 0.6 amp, 100 Vac @ 0.1 amp
EXCITATION CURRENT
READING RANGE 0 – 2 Amperes; Accuracy: ±1mA, ±2% of reading (±1 digit)
PHASE-ANGLE
MEASUREMENT 0 – 360 degrees; Accuracy: ±0.2 degrees ( ±1 digit)
DISPLAY Back-lit LCD screen (20 Characters by 4 Lines); Viewable in bright sunlight
and low-light levels
PRINTER Built-in 4.5-inch wide thermal printer
COMPUTER INTERFACE RS-232C (19,200 baud) port
PC SOFTWARE Windows
®
XP/Vista-based Transformer Turns-Ratio Analyzer application is
included with purchase price
INTERNAL TEST RECORD
STORAGE Stores 200 complete transformer test records. Each test record includes nameplate voltage, winding turns-ratios, excitation current, and winding
phase angle.
INTERNAL TEST PLAN
STORAGE Stores up to 128 transformer test plans
SAFETY UL Certified (UL 61010A-1), CAN/CSA Certified (C22.2 No. 1010.1-92)
ENVIRONMENT Operating: -10° to 50° C (15° to +122° F); Storage: -30° C to 70° C (-22° to
+158° F)
HUMIDITY (MAX) 90% RH @ 40˚C (104˚F) non-condensing
ALTITUDE (MAX) 2000m (6562 ft) to fully safety specifications
CABLES One 15-foot single-phase cable set, One 15-foot 3-phase cable set, One 25-
foot extension cable set, One cable-carrying duffel bag included
OPTIONS Transportation case, transformer tap-changer remote control device
WARRANTY One year on parts and labor
NOTE
The above specifications are valid at nominal operating voltage and at a
temperature of 25°C (77°F). Specifications may change without prior notice.

ATRT-03, ATRT-03A, AND ATRT-03B USER’S MANUAL REV 2
5
1.2.2. ATRT-03A Technical Specifications
Table 2. ATRT-03A Technical Specifications
TYPE Portable, lightweight, automatic, battery-powered three-phase transformer
turns-ratio meter
PHYSICAL SPECIFICATIONS 19”W x 7”H x 15”D (48.2cm x 17.8 cm x 38.1 cm); Weight: 25 lbs (11.3 kg)
INPUT POWER 3 amps, 85 – 264 Vac or 110 – 370 Vdc or 12 Vdc
BATTERIES Two 12Vdc/2AH, rechargeable Sealed Lead Acid batteries (up to 3-hours
operation)
MEASUREMENT METHOD ANSI/IEEE C57.12.90
RATIO-MEASURING RANGE 0.8 – 15,000 (5-digit resolution)
TURNS-RATIO ACCURACY 0.8 – 1999: ±0.1%, 2,000 – 3,999: ±0.25%, 4,000 – 15,000: ±1% @ 8 Vac
0.8 – 1999: ±0.1%, 2,000 – 3,999: ±0.20%, 4,000 – 15,000: ±1% @ 40 Vac
0.8 – 1999: ±0.1%, 2,000 – 3,999: ±0.15%, 4,000 – 15,000: ±1% @ 100 Vac
ADJUSTMENT None required
TEST VOLTAGES 8 Vac @ 350 mA, 40 Vac @ 70 mA, 100 Vac @ 20 mA
EXCITATION CURRENT
READING RANGE 0 – 2 Amperes; Accuracy: ±1mA, ±2% of reading (±1 digit)
PHASE-ANGLE
MEASUREMENT 0 – 360 degrees; Accuracy: ±0.2 degrees ( ±1 digit)
DISPLAY Back-lit LCD screen (20 Characters by 4 Lines); Viewable in bright sunlight
and low-light levels
PRINTER Built-in 4.5-inch wide thermal printer
COMPUTER INTERFACE RS-232C (19,200 baud) port
PC SOFTWARE Windows
®
XP/Vista-based Transformer Turns-Ratio Analyzer application is
included with purchase price
INTERNAL TEST RECORD
STORAGE Stores 200 complete transformer test records. Each test record includes nameplate voltage, winding turns-ratios, excitation current, and winding
phase angle.
INTERNAL TEST PLAN
STORAGE Stores up to 128 transformer test plans
SAFETY Designed to meet UL 61010A-1 and CAN/CSA C22.2 No. 1010.1-92
standards
ENVIRONMENT Operating: -10˚to 50˚C (15˚to +122˚F); Storage: -30˚C to 70˚C (-22˚to
+158˚F)
HUMIDITY (MAX) 90% RH @ 40˚C (104˚F) non-condensing
ALTITUDE (MAX) 2000m (6562 ft) to fully safety specifications
CABLES One 15-foot single-phase cable set, One 15-foot 3-phase cable set, One 25-
foot extension cable set, One cable-carrying duffel bag included
OPTIONS Transportation case, transformer tap-changer remote control device
WARRANTY One year on parts and labor
NOTE
The above specifications are valid at nominal operating voltage and at a
temperature of 25°C (77°F). Specifications may change without prior notice.

REV 2 ATRT-03, ATRT-03A, AND ATRT-03B USER’S MANUAL
6
1.2.3. ATRT-03B Technical Specifications
Table 3. ATRT-03B Technical Specifications
TYPE Portable, lightweight, automatic, three-phase transformer turns-ratio meter
PHYSICAL SPECIFICATIONS 17”W x 7”H x 13”D (43.2cm x 17.8 cm x 33.0 cm); Weight: 13 lbs (5.9 kg)
INPUT POWER 3 amps, 110 – 120 Vac or 220 – 240 Vac (selectable), 50/60 Hz
MEASUREMENT METHOD ANSI/IEEE C57.12.90
RATIO-MEASURING RANGE 0.8 – 15,000 (5-digit resolution)
TURNS-RATIO ACCURACY 0.8 – 1999: ±0.1%, 2,000 – 3,999: ±0.25%, 4,000 – 15,000: ±1% @ 8 Vac
0.8 – 1999: ±0.1%, 2,000 – 3,999: ±0.20%, 4,000 – 15,000: ±1% @ 40 Vac
0.8 – 1999: ±0.1%, 2,000 – 3,999: ±0.15%, 4,000 – 15,000: ±1% @ 100 Vac
ADJUSTMENT None required
TEST VOLTAGES 8 Vac @ 1 amp, 40 Vac @ 0.6 amp, 100 Vac @ 0.1 amp
EXCITATION CURRENT
READING RANGE 0 – 2 Amperes; Accuracy: ±1mA, ±2% of reading (±1 digit)
PHASE-ANGLE
MEASUREMENT 0 – 360 degrees; Accuracy: ±0.2 degrees ( ±1 digit)
DISPLAY Back-lit LCD screen (20 Characters by 4 Lines); Viewable in bright sunlight
and low-light levels
COMPUTER INTERFACE RS-232C (19,200 baud) port
PC SOFTWARE Windows
®
XP/Vista-based Transformer Turns-Ratio Analyzer application is
included with purchase price
INTERNAL TEST RECORD
STORAGE Stores 200 complete transformer test records. Each test record includes nameplate voltage, winding turns-ratios, excitation current, and winding
phase angle.
INTERNAL TEST PLAN
STORAGE Stores up to 128 transformer test plans
SAFETY Designed to meet UL 61010A-1 and CAN/CSA C22.2 No. 1010.1-92
standards
ENVIRONMENT Operating: -10˚to 50˚C (15˚to +122˚F); Storage: -30˚C to 70˚C (-22˚to
+158˚F)
HUMIDITY (MAX) 90% RH @ 40˚C (104˚F) non-condensing
ALTITUDE (MAX) 2000m (6562 ft) to fully safety specifications
CABLES One 15-foot single-phase cable set, One 15-foot 3-phase cable set, One 25-
foot extension cable set, One cable-carrying duffel bag included
OPTIONS Transportation case, transformer tap-changer remote control device
WARRANTY One year on parts and labor
NOTE
The above specifications are valid at nominal operating voltage and at a
temperature of 25°C (77°F). Specifications may change without prior notice.

ATRT-03, ATRT-03A, AND ATRT-03B USER’S MANUAL REV 2
7
1.3 Controls and Indicators
The ATRT-03, ATRT-03A, and ATRT-03B controls and indicators are shown in Figure 1, Figure 2,
and Figure 3, respectively. A leader line with an index number points to each control and
indicator, which is cross-referenced to a functional description in the corresponding table. The
purpose of the controls and indicators may seem obvious, but users should familiarize
themselves with them before using the ATRT. Accidental misuse of the controls will usually
cause no serious harm. Users should also familiarize themselves with the safety summary
information found on the front page of this User’s Manual.
Figure 1. ATRT-03 Controls and Indicators

REV 2 ATRT-03, ATRT-03A, AND ATRT-03B USER’S MANUAL
8
Table 4. Functional Descriptions of ATRT-03 Controls and Indicators
Item
Number Panel Markings Functional Description
1 Back-lit LCD screen (20 characters by 4 lines), viewable in bright
sunlight and low-light levels.
2 H H voltage connector.
3 X X voltage connector.
4 4.5-inch wide thermal printer.
5 120/240 Vac, 1A, 50/60Hz
Fuse: 250Vac, 2A Fast-Blow Input power connector and fused power switch with third-wire safety ground.
6 Ground stud for connecting to sub-station ground.
7 RS-232C RS-232C PC interface connector.
8 TEST
IN
PROGRESS
This LED flashes in response to commands or when a test voltage is
applied to the test transformer.
9 Rugged alpha-numeric keypad.
10 EMERGENCY
TURN OFF
“PUSH”
Emergency turn off test voltage switch.

ATRT-03, ATRT-03A, AND ATRT-03B USER’S MANUAL REV 2
9
Figure 2. ATRT-03A Controls and Indicators

REV 2 ATRT-03, ATRT-03A, AND ATRT-03B USER’S MANUAL
10
Table 5. Functional Descriptions of ATRT-03A Controls and Indicators
Item
Number Panel Markings Functional Description
1 Back-lit LCD screen (20 characters by 4 lines), viewable in bright
sunlight and low-light levels.
2 H H voltage connector.
3 X X voltage connector.
4 4.5-inch wide thermal printer.
5 POWER Power switch.
6 120/240 Vac, 1A, 50/60Hz
Fuse: 250Vac, 2A Fast-Blow Input power connector with third-wire safety ground.
7 GROUND Ground stud for connecting to sub-station ground.
8 CHARGE LED is lit when internal batteries are being charged.
9 +12V
GROUND 12 VDC input connectors.
10 RS-232C RS-232C PC interface connector.
11 Rugged alpha-numeric keypad.
12 TEST
IN
PROGRESS
This LED flashes in response to commands or when a test voltage is
applied to the test transformer.
13 EMERGENCY
TURN OFF
“PUSH”
Emergency turn off test voltage switch.

ATRT-03, ATRT-03A, AND ATRT-03B USER’S MANUAL REV 2
11
Figure 3. ATRT-03B Controls and Indicators

REV 2 ATRT-03, ATRT-03A, AND ATRT-03B USER’S MANUAL
12
Table 6. Functional Descriptions of ATRT-03B Controls and Indicators
Item
Number Panel Markings Functional Description
1 Back-lit LCD screen (20 characters by 4 lines), viewable in bright
sunlight and low-light levels.
2 H H voltage connector.
3 X X voltage connector.
4 120/240 Vac, 1A, 50/60Hz
Fuse: 250Vac, 2A Fast-Blow Input power connector and fused power switch with third-wire safety ground.
5 Ground stud for connecting to sub-station ground.
6 RS-232C RS-232C PC interface connector.
7 TEST
IN
PROGRESS
This LED flashes in response to commands or when a test voltage is
applied to the test transformer.
8 Rugged alpha-numeric keypad.
9 EMERGENCY
TURN OFF
“PUSH”
Emergency turn off test voltage switch.

ATRT-03, ATRT-03A, AND ATRT-03B USER’S MANUAL REV 2
13
2.0 PRE-TEST SETUP
2.1 ATRT-03 and ATRT-03B Operating Voltages
The ATRT-03 and ATRT-03B’s voltage is preset at the factory and is selectable between 110-120
Vac, 50/60 Hz or 220-240 Vac, 50/60 Hz. The voltage is set by placing jumpers on the reference
transformer as listed in Table 7 and illustrated in Figure 4.
Table 7. Voltage Selection Jumper Settings
Voltage
Selection Transformer Jumpers
110
–
120 Vac Pin 1 & 3, Pin 2 & 4
220
–
240 Vac Pin 2 & 3
Figure 4. Voltage Selection Jumper Location and Settings
2.2 ATRT-03A Operating Voltages
The ATRT-03A uses a special switching power supply. The input AC receptacle can accept
voltages that range from 90-264 Vac or 110-240 Vdc. The ATRT-03A can also accept 12 Vdc
from a battery via the front panel jacks.
2.3 LCD Screen Contrast Control
To increase the LCD screen contrast, press and hold the [PAPER ∧Contrast] key for two
seconds. Release the button when the desired contrast level has been reached.
To decrease the LCD screen contrast, press and hold the [PAPER ∨Contrast] key for two
seconds. Release the button when the desired contrast level has been reached.

REV 2 ATRT-03, ATRT-03A, AND ATRT-03B USER’S MANUAL
14
2.4 Printer Paper Control (ATRT-03 and ATRT-03A Only)
To advance the thermal printer paper, press and release the [PAPER ∧Contrast] key.
To retract the thermal printer paper, press and release the [PAPER ∨Contrast] key.
2.5 Printer Paper (ATRT-03 and ATRT-03A Only)
The ATRT-03 and ATRT-03A’s built-in thermal printers use 4.5-inch wide thermal paper for
printing test results. To maintain the highest print quality and to avoid paper jams, the use of
thermal paper supplied by Vanguard Instruments Company is highly recommended. Additional
paper can be ordered from the following sources:
Vanguard Instruments Co, Inc.
1520 S. Hellman Avenue
Ontario, CA 91761
Tel: [phone]
Fax: [phone]
Part Number: VIC TP-4 paper
BG Instrument Co.
13607 E. Trent Avenue
Spokane, WA 99216
Tel: [phone]
Fax: [phone]
Part Number: VIC TP-4 paper

ATRT-03, ATRT-03A, AND ATRT-03B USER’S MANUAL REV 2
15
3.0 OPERATING PROCEDURES
The ATRT-03 should always be grounded with the provided ground cable before connecting H
and X cables. The transformer bushings should also be grounded before connecting test leads
to the transformer. This will prevent inducing any voltages into the ATRT-03. All transformer
bus connections must be removed, and the transformer must be isolated before performing
any tests. Typical transformer connection diagrams are illustrated in the sections below.
3.1 Connection Diagrams
3.1.1. Typical Front Panel Connections
Figure 5. Typical Front Panel Cable Connections