Vanguard EZCT-S2A User Manual
TM
EZCT S2A
DIGITAL CURRENT-TRANSFORMER TESTER
USER’S MANUAL
Vanguard Instruments Company, Inc.
1520 S. Hellman Ave.
Ontario, California 91761, USA
TEL: (909) 923-9390
FAX: (909) 923-9391
March 2014
Revision 1
EZCT S2A USER’S MANUAL REV 1
SAFETY SUMMARY
FOLLOW EXACT OPERATING PROCEDURES
Any deviation from the procedures described in this User’s Manual may create one or more
safety hazards, may damage the EZCT S2A, or cause errors in the test results. Vanguard
Instruments Company, Inc. assumes no liability for unsafe or improper use of the EZCT S2A.
All safety precautions provided in this manual must be observed during all phases of testing
including test preparation, test lead connection, actual testing, and test lead disconnection.
SAFETY WARNINGS AND CAUTIONS
The EZCT S2A can produce a voltage up to 1,500 Vac that can cause severe injury and/or
equipment damage. Due to this reason, the EZCT S2A shall be used only by trained operators.
The EZCT S2A’s X output terminals are rated to 1,500 Vac working voltage. Any voltage above
1,500 Vac will damage the input circuitry.
All devices under test shall be off-line and fully isolated. Never attempt to test any current
transformer still connected to a circuit. All current transformer terminals shall be isolated
before conducting any test with the EZCT S2A.
Always ground the EZCT S2A to a substation ground before connecting the test cables to a
transformer.
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 EZCT S2A 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.
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TABLE OF CONTENTS
CONVENTIONS USED IN THIS DOCUMENT ....................................................................... 1
1.0 INTRODUCTION .................................................................................................................. .. 2
1.1 General Description and Features ................................................................................... 2
1.2 Furnished Accessories ...................................................................................................... 3
1.3 Technical Specifications ................................................................................................... 4
1.4 EZCT S2A Controls and Indicators .................................................................................... 5
2.0 PRE-TEST SETUP ................................................................................................................... 7
2.1 Operating Voltages .......................................................................................................... 7
2.2 LCD Screen Contrast Control ............................................................................................ 7
2.3 Printer Paper Control ....................................................................................................... 7
2.4 Printer Paper .................................................................................................................... 7
3.0 OPERATING PROCEDURES ................................................................................................... 9
3.1 EZCT S2A Cable Connections ........................................................................................... 9
3.2 Performing Tests ............................................................................................................ 11
3.2.1. Entering Test Record Header Information ............................................................. 11
3.2.2. Performing Excitation and Ratio Tests ................................................................... 14
3.3 Working With Test Records ........................................................................................... 24
3.3.1. Restoring and Printing a Test Record From Flash EEPROM ................................... 24
3.3.2. Restoring and Printing a Test Record From a USB Flash Drive .............................. 29
3.3.3. Printing a Restored Test Record ............................................................................. 32
3.3.4. Printing a Directory of Test Records Stored in the EZCT S2A’s Memory ............... 34
3.3.5. Erasing Test Records From the Flash EEPROM ...................................................... 37
3.3.6. Erasing Test Records From a USB Flash Drive ........................................................ 40
3.4 Working With Test Plans ................................................................................................ 43
3.4.1. Extracting the Test Plan From a Test Record ......................................................... 43
3.4.2. Printing a Directory of Test Plans Stored in the EZCT S2A’s Memory .................... 45
3.4.3. Printing a Directory of Test Plans Stored in a USB Flash Drive .............................. 47
3.4.4. Printing a Test Plan ................................................................................................. 49
3.4.5. Erasing Test Plans From the Flash EEPROM ........................................................... 51
3.4.6. Erasing Test Plans From a USB Flash Drive ............................................................. 54
3.4.7. Loading a Test Plan from the EZCT S2A’s Flash EEPROM ....................................... 57
3.4.8. Loading a Test Plan from a USB Flash Drive ........................................................... 59
3.4.9. Running a Test Using a Loaded Test Plan ............................................................... 61
3.4.10. Unloading a Test Plan from the Working Memory ................................................ 66
4.0 CHANGING SETUP PARAMETERS ....................................................................................... 67
4.1 Setting the Knee Point Marker ...................................................................................... 67
4.2 Enabling and Disabling the Buried CT in Transformer Delta Option ............................. 70
4.2.1. Enabling the Buried CT in Transformer Delta Option............................................. 70
4.2.2. Disabling the Buried CT in Transformer Delta Option ............................................ 71
4.3 Setting the Clock ............................................................................................................ 75
4.4 Printing Raw Memory Buffer Data ................................................................................. 76
5.0 DIAGNOSTICS, VERIFICATION, AND TROUBLESHOOTING ................................................. 78
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EZCT S2A USER’S MANUAL REV 1
5.1 Performing a Diagnostics Test ....................................................................................... 78
5.2 Verifying the EZCT S2A’s Vx Sense Circuit Using an External Meter .............................. 80
5.3 Verifying the EZCT S2A’s Ix Sense Circuit Using an External Meter ............................... 81
5.4 Quickly Verifying the EZCT S2A’s Turns Ratio Circuit ..................................................... 82
5.5 Troubleshooting Guide .................................................................................................. 83
6.0 UPGRADING FIRMWARE .................................................................................................... 84
7.0 Appendix A - Calculating Turns Ratio on a Shunt Reactor ................................................. 87
LIST OF TABLES
Table 1. EZCT S2A Technical Specifications .................................................................................... 4
Table 2. Functional Descriptions of EZCT S2A Controls and Indicators .......................................... 6
Table 3. Descriptions of Tabulated Test Results Elements ........................................................... 22
Table 4. Description of Test Plan Elements .................................................................................. 50
LIST OF FIGURES
Figure 1. EZCT S2A Controls and Indicators .................................................................................... 5
Figure 2. Typical EZCT S2A Excitation and Ratio Test Cable Connection ........................................ 9
Figure 3. Bushing CT Connection on Delta Transformer .............................................................. 10
Figure 4. Bushing CT Connection on Y Transformer ..................................................................... 10
Figure 5. Typical EZCT S2A Tabulated Report Printout ................................................................. 21
Figure 6. Typical EZCT S2A Graphic Report ................................................................................... 23
Figure 7. Typical Internal Test Record Directory Printout ............................................................ 36
Figure 8. Typical EZCT S2A Flash EEPROM Test Plan Directory Printout ...................................... 46
Figure 9. Typical USB Flash Drive Test Plan Directory Printout .................................................... 48
Figure 10. Typical Test Plan Printout ............................................................................................ 50
Figure 11. Graphic Report Showing Knee Point Marker ............................................................... 69
Figure 12. Buried CT in a Delta Transformer Illustration 1 ........................................................... 73
Figure 13. Buried CT in a Delta Transformer Illustration 2 ........................................................... 73
Figure 14. Sample Raw Data Printout ........................................................................................... 77
Figure 15. EZCT S2A Vx Verification Test Connections .................................................................. 80
Figure 16. EZCT S2A Ix Verification Test Connections ................................................................... 81
Figure 17. EZCT S2A Turns Ratio Verification Test Connections ................................................... 82
Figure 18 ....................................................................................................................................... 87
Figure 19 ....................................................................................................................................... 88
Figure 20 ....................................................................................................................................... 89
Figure 21 ....................................................................................................................................... 90
Figure 22 ....................................................................................................................................... 91
Figure 23 ....................................................................................................................................... 92
Figure 24 ....................................................................................................................................... 93
Figure 25 ....................................................................................................................................... 93
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CONVENTIONS USED IN THIS DOCUMENT
This document uses the following conventions:
•
A key or switch on the EZCT S2A is indicated as
[KEY]
and
[SWITCH].
Menu options are referenced as (MENU OPTION).
•
Screen and menu names are referenced as “SCREEN/MENU NAME”.
•
The terms “test record” and “test shot” are used interchangeably.
•
• EZCT S2A LCD screen output is shown as:
1. OPTION 1
2. OPTION 2
3. OPTION 3
4. OPTION 4
5. OPTION 5
• When instructions are provided, the menu item that should be selected is shown in bold as
shown below (option 3 should be selected):
1. OPTION 1
2. OPTION 2
3. OPTION 3
4. OPTION 4
5. OPTION 5
• Warning messages are indicated as:
Warning message
WARNING
• Important notes are indicated as:
Note details
NOTE
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EZCT S2A USER’S MANUAL REV 1
1.0 INTRODUCTION
1.1 General Description and Features
The EZCT S2A is Vanguard’s third-generation, microprocessor-based, current transformer test
set. The EZCT S2A can perform the current transformer (CT) excitation, CT current-ratio, and
winding polarity tests automatically. The EZCT S2A automatically raises and lowers the
excitation test voltage without any operator intervention. With up to 1500 Vac excitation test
voltage available, the EZCT S2A can easily perform excitation tests on very large CT’s.
Excitation Test
The CT excitation test is performed using the ANSI/IEEE C57.13.1, IEC 60044-1 test method. The
test voltage range for the CT excitation test (50 Vac, 250 Vac, 500 Vac, or 1500 Vac) can be
selected, and then the test voltage is raised and lowered automatically by the EZCT S2A. The
test voltage and current data are collected and stored in the unit’s internal memory. Up to 10
CT excitation and current-ratio tests can be stored in one test record. IEEE-30, IEEE-45, ANSI/IEC
60044-1 (10/50) knee point voltages are also calculated and printed on the test report. Once
the test is completed, test results can be printed and excitation curves can be plotted on the
built-in 4.5-inch wide thermal printer.
CT Ratio and Polarity Tests
The EZCT S2A determines the CT current-ratio using the ANSI/IEEE C57.12.90 measurement
method. A test voltage is applied to the CT’s secondary terminals and the induced voltage is
measured through the CT’s H1 and H2 terminals. The CT current-ratio and polarity are displayed
on the screen and stored in memory. The current-ratio measuring range is from 0.8 to 5,000.
The CT winding polarity is displayed as a “+” sign (in-phase) or a “-” sign (out-of-phase) and is
annotated with the phase angle in degrees.
User Interface and Display
The EZCT S2A features a back-lit LCD screen (240 x 128 dot graphic) that is viewable in both
bright sunlight and low-light levels. A rugged, alpha-numeric, membrane keypad is used to
control the unit.
Built-in Thermal Printer
A built-in 4.5-inch wide thermal printer can print the current transformer test report and plot
the excitation curves.
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Test Record Header Information
The test record header information can include the company name, substation name, circuit ID,
manufacturer, CT serial number, operator’s name, and test record comments. In addition to the
test record header, a 20-character test description for each test in the record can also be
entered.
Internal Test Record Storage Capacity
The EZCT S2A can store up to 140 test records in Flash EEPROM. Each test record may contain
up to 10 excitation curves, current-ratio readings, and winding polarity readings. Test records
can be recalled and printed on the built-in thermal printer.
Internal Test Plan Storage Capacity
The EZCT S2A can store up to 128 CT test plans in Flash EEPROM. A test plan defines the
excitation test voltage and current selection, CT nameplate ratio, and CT winding terminal
connection instructions for each test. Up to 10 test definitions can be stored in each test plan.
The use of a test plan greatly simplifies the CT testing process since it also provides instructions
for making the proper CT cable connections. Test plans can be created on the EZCT S2A itself or
created on a PC and downloaded to the EZCT S2A via the unit’s built-in RS-232C or USB port.
External Data Storage
The EZCT S2A features a standard USB Flash drive interface that makes it very convenient to
store and transfer test records and test plans. By plugging in a USB Flash drive, you can quickly
transfer your test records and test plans between a computer and the EZCT S2A without the
need to connect the unit to the computer.
Computer Interface
The EZCT S2A can be used as a stand-alone unit or can be computer-controlled via the built-in
RS-232C or USB interfaces. A Windows® XP/Vista-based Current Transformer Analysis software
application is provided with each EZCT S2A. This software can be used to retrieve test records
from the EZCT S2A, create test plans, download test plans to the EZCT S2A, and can also be
used to run CT tests from the PC. Tabulated test records can be exported in Microsoft® Excel
format.
1.2 Furnished Accessories
The EZCT S2A comes furnished with the following:
• 1 Power Cord
• 2 20-foot X Cable Sets
• 1 35-foot H Cable Set
• One RS-232C serial cable
• One USB cable
• Ground Cables
• Cable carrying duffel bag
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EZCT S2A USER’S MANUAL REV 1
®
1.3 Technical Specifications
Table 1. EZCT S2A Technical Specifications
TYPE Portable current transformer test set
PHYSICAL SPECIFICATIONS 16.8”W x 12.6”H x 12”D (42.7 cm x 32 cm x 26.9 cm); Weight: 55 lbs (25 kg)
INPUT POWER 100 – 120 Vac or 200 – 240 Vac (factory pre-set), 50 Hz/60 Hz
MEASUREMENT METHOD ANSI/IEEE C57.12.90, IEC 60044-1 and ANSI/IEEE C57.13.1 standards
TEST OUTPUT VOLTAGES 0 – 50 Vac @ 10A max, 0 – 250 Vac @ 10A max
0 – 500 Vac @ 5A max, 0 – 1500 Vac @ 1.2A max
VOLTAGE READING RANGE 0 – 2,200 Vac; Accuracy: ±1.0% of reading, ±1 volt
CURRENT READING RANGE 0 – 10A; Accuracy: ±1.0% of reading, ±0.02A
CURRENT-RATIO RANGE 0.8 – 999: 0.1%, 1000 – 1999: 0.3%, 2000 – 5000: 1%
PHASE ANGLE
MEASUREMENT
DISPLAY Back-lit LCD Screen (240 x 128 dot graphic; 114mm x 64mm); viewable in
PRINTER Built-in 4.5-inch wide thermal printer
COMPUTER INTERFACES One RS-232C port (115k baud), one USB port
EXTERNAL DATA STORAGE One USB Flash drive interface port (Flash drive not included)
PC SOFTWARE Windows
INTERNAL TEST RECORD
STORAGE
INTERNAL TEST PLAN
STORAGE
SAFETY Designed to meet UL 61010A-1 and CAN/CSA C22.2 No. 1010.1-92
ENVIRONMENT Operating: -10˚ to 50˚ C (15˚F to +122˚ F); Storage: -30˚ C to 70˚ C (-22˚F to
HUMIDITY (MAX) 90% RH @ 40˚ C (104˚ F) non-condensing
ALTITUDE (MAX) 2000m (6562 ft) to fully safety specifications
CABLES Two 20-foot X cable sets, One 35-foot H cable set, power cord, One cable-
WARRANTY One year on parts and labor
0 - 360 degrees; Accuracy: ±1.0 degree
bright sunlight and low-light levels
XP/Vista-based CT Analysis software is included with purchase
price
Stores 140 test records. Each test record may contain up to 10 sets of
excitation, resistance and ratio data
Stores 128 test plans. Each test plan can store 10 excitation test voltage and
current settings
standards
+158˚ F)
carrying duffel bag
The above specifications are valid at nominal operating voltage and at a
temperature of 25°C (77°F). Specifications may change without prior notice.
NOTE
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1.4 EZCT S2A Controls and Indicators
The EZCT S2A’s controls and indicators are shown in Figure 1 below. A leader line with an index
number points to each control and indicator, which is cross-referenced to a functional
description in Table 2. The table describes the function of each item on the control panel. The
purpose of the controls and indicators may seem obvious, but users should become familiar
with them before using the EZCT S2A. Accidental misuse of the controls will usually cause no
serious harm. Users should also be familiar with the safety summary found on the front page of
this User’s Manual.
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Figure 1. EZCT S2A Controls and Indicators
EZCT S2A USER’S MANUAL REV 1
Table 2. Functional Descriptions of EZCT S2A Controls and Indicators
Item
Number
1
2
3
4
5
6
7
8
9
10
11
12
13
Panel Markings Functional Description
Current transformer excitation voltage connector. The EZCT S2A’s X output
X
H Current transformer primary input test cable connector.
Built-in 4.5-inch wide thermal printer.
110-120 Vac,
12A, 50-60Hz
Power receptacle.
GROUND Ground terminal.
Back-lit LCD Screen (240 x 128 dot graphic; 114mm x 64mm).
RS-232C RS-232C PC interface. Baud rate is set for 115KB, 8 data bits, 2 stop bits.
USB PC USB PC interface.
Rugged alpha-numeric keypad.
USB MEM USB Flash drive interface port
HIGH VOLTAGE
PRESENT
EMERGENCY
TURN OFF
“PUSH”
terminal is rated to 1500 Vac working voltage. Any voltage above 1500 Vac
will damage the input circuitry.
Power switch with built-in circuit breaker.
Test voltage presence indicator.
Emergency turn off switch.
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2.0 PRE-TEST SETUP
2.1 Operating Voltages
The EZCT S2A’s operating voltage is preset at the factory for 100-120 Vac, 50/60 Hz or 200-240
Vac, 50/60 Hz.
2.2 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.
2.3 Printer Paper Control
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.
2.4 Printer Paper
The EZCT S2A’s built-in thermal printer uses 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: 909-923-9390
Fax: 909-923-9391
Part Number: VIC TP-4 paper
BG Instrument Co.
13607 E. Trent Avenue
Spokane, WA 99216
Tel: 509-893-9881
Fax: 509-893-9803
Part Number: VIC TP-4 paper
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EZCT S2A USER’S MANUAL REV 1
2.5 Replacing the Thermal Printer Paper
The roll of thermal paper is housed inside a dispenser underneath the printer cover. To replace
the paper, follow the steps below:
• Unscrew the two large printer cover screws and remove the printer cover.
• Remove the leftover thermal paper roll from the paper holder.
• Unroll the new thermal paper roll.
• Feed the thermal paper into the slot between the paper pocket and the rubber roller.
The printer will automatically pull the paper under the thermal head.
• Place the paper roll into the paper holder.
• Lift the thermal head and align the thermal paper if necessary.
• Re-install the printer cover.
Thermal paper has a chemical coating on one side of the paper. This side should be
facing the thermal print head. Incorrect paper loading may result in blank output on
NOTE
the thermal paper.
The thermal paper will show a red stripe to indicate that the roll is about to run out
of paper.
2.6 Computer Interface Ports
The EZCT S2A features one USB and one RS-232C PC interface port. A Windows-based “Current
Transformer Analysis” software application is supplied with the EZCT S2A. For further
information, please see the Software User’s Manual.
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3.0 OPERATING PROCEDURES
3.1 EZCT S2A Cable Connections
Always connect the EZCT S2A to the substation ground before connecting any test cables. The X
cable connections are required to run the current transformer excitation test. The H and X cable
connections are required to run the transformer turns-ratio test. A typical excitation and ratio
test connection is shown in Figure 2. Transformer bushing CT connections for Delta and Y
transformers are shown in Figure 3 and Figure 4, respectively.
Figure 2. Typical EZCT S2A Excitation and Ratio Test Cable Connection
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EZCT S2A USER’S MANUAL REV 1
Figure 3. Bushing CT Connection on Delta Transformer
Figure 4. Bushing CT Connection on Y Transformer
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3.2 Performing Tests
3.2.1. Entering Test Record Header Information
You can enter the test record header information before performing tests. The record header
includes identifying information such as the company, station, circuit, model number, etc. Once
the header information has been entered, it will apply to all subsequent test records. To enter
the header information:
a. When the unit is turned on and the firmware has been loaded, you will be presented
with the “START-UP” menu as shown below:
1. RUN TEST 02/14/10
2. SETUP 10:14:25
3. TEST PLANS
4. DIAGNOSTIC
Press the [2] key (SETUP).
b. The following screen will be displayed:
1. RECORD ID
2. PRINT RECORD
3. RECORD DIRECTORY
4. SAVE/RES RECORD
5. ERASE RECORD
6. NEXT PAGE
Press the [1] key (RECORD ID)
c. The following screen will be displayed:
COMPANY:
vanguard
↑↓ TO POSITION
"enter" to accept
Type the company name using the alpha-numeric keypad.
When pressing a key, the corresponding number on the key will be displayed first.
Pressing the key again will display the first letter on the key. Pressing the key again will
display the second letter on the key. For example, to type the letter “A”, you must press
[2] key twice. To erase the character at the cursor position, press the [CLEAR] key.
the
Press the
∨ Contrast]
[PAPER ∧ Contrast] key to move to the next character. Press the [PAPER
key to move to the previous character. Press the [ENTER] key when you
are done typing the company name.
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d. The following screen will be displayed:
STATION:
LAB
↑↓ TO POSITION
"enter" to accept
Type the station name using the alpha-numeric keypad and then press the [ENTER]
key.
e. The following screen will be displayed:
CIRCUIT:
CIRCUIT 1
↑↓ TO POSITION
"enter" to accept
EZCT S2A USER’S MANUAL REV 1
Type the circuit information using the alpha-numeric keypad and then press the
[ENTER] key.
f. The following screen will be displayed:
MANUFACTURER:
ABB
↑↓ TO POSITION
"enter" to accept
Type the manufacturer name using the alpha-numeric keypad and then press the
[ENTER] key.
g. The following screen will be displayed:
MODEL:
↑↓ TO POSITION
"enter" to accept
Type the model information using the alpha-numeric keypad and then press the
[ENTER] key.
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h. The following screen will be displayed:
SERIAL NUMBER:
↑↓ TO POSITION
"enter" to accept
Type the serial number using the alpha-numeric keypad and then press the [ENTER]
key.
i. The following screen will be displayed:
COMMENTS:
no comment
↑↓ TO POSITION
"enter" to accept
Enter any relevant comments using the alpha-numeric keypad and then press the
[ENTER] key.
j. The following screen will be displayed:
OPERATOR:
TA
↑↓ TO POSITION
"enter" to accept
Type the operator’s name using the alpha-numeric keypad and then press the [ENTER]
key. All header information will be saved, and you will be returned to the “START-UP”
menu.
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EZCT S2A USER’S MANUAL REV 1
3.2.2. Performing Excitation and Ratio Tests
The following procedure describes the general steps for performing excitation and ratio tests.
a. When the EZCT S2A is turned on, it will first go through a start-up cycle and load the
firmware. Then the “START-UP” menu will be displayed as shown below:
1. RUN TEST 02/14/10
2. SETUP 10:24:25
3. TEST PLANS
4. DIAGNOSTIC
Press the [1] key (RUN TEST) to start a test.
b. The following screen will be displayed:
1. EXCITATION & RATIO
2. excitation only
3. ratio only
Select the test type by pressing the corresponding key ([1] - [3])
c. The following screen will be displayed:
SELECT TAP:
1. X1-X2
2. X1-X3
3. X1-X4
4. X1-X5
5. NEXT PAGE
Select the tap connection by pressing the corresponding key (
[1] - [4]). If the tap
connection is not listed, press the [5] key to view the next page of options.
d. The following screen will be displayed:
HOOK CABLES TO CT:
X1 CABLE TO CT-X1
X2 CABLE TO CT-X2
"ENTER" TO CONTINUE
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The cable connection information displayed depends on your selection in step
c.
NOTE
Press the
[ENTER]
key to continue.
e. If the selected test included an excitation test, the following screen will be displayed:
SELECT VOLTAGE RANGE:
1. 50V
2. 250V
3. 500V
4. 1500V
Select the test voltage range by pressing the corresponding key (
[1]
-
[4]
).
f. If the selected test included an excitation test, the following screen will be displayed:
SET TEST CURRENT:
1. 0.2A
2. 0.5A
3. 1A
4. 2A
5. 5A
6. 10A
Select the maximum test current for the excitation test by pressing the corresponding
key (
[1] - [6]
).
Most CT’s will saturate before the excitation current reaches 1A. To reduce
stress on CT’s, a maximum test current of 1A is recommended.
NOTE
g. If the selected test included a ratio test, the following screen will be displayed:
XFMR NAME PLATE RAT.
1. YES
2. NO
1. YES
Press the
[1]
key if you would like to enter the CT nameplate values. The
following screen will be displayed:
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EZCT S2A USER’S MANUAL REV 1
ENTER PLATE RATIO:
0 :
Type the first number using the keypad.
You can press the
Press the
ENTER PLATE RATIO:
80 : 0.0
[ENTER] key. The following screen will be displayed:
[CLEAR] key to restart a field entry if necessary.
Type the second number using the keypad. The screen will be updated as shown:
ENTER PLATE RATIO:
80 : 1.0
Press the [ENTER] key. Continue to step h.
2. NO
Press the [2] key if you do not want to enter the CT nameplate values. Continue
to step h.
h. The following screen will be displayed:
ENTER TEST 1 NOTE:
_
↑↓ to position
"ENTER" TO ACCEPT
Use the alpha-numeric keys on the keypad to enter a test note. The test note field is 20
characters long. One test note can be saved for each test.
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When pressing a key, the corresponding number on the key will be displayed first.
Pressing the key again will display the first letter on the key. Pressing the key again will
display the second letter on the key. For example, to type the letter “A”, you must press
the
[2]
key twice. To erase the character at the cursor position, press the
Press the
[PAPER ∨ Contrast]
[PAPER ∧ Contrast]
key to move to the previous character. Press the
when you are done typing the note.
i. The following screen will be displayed:
TEST 1 parameters:
1500V 1.0A x1-x2
"START" to begin
[CLEAR]
button to move to the next character. Press the
[ENTER]
key.
key
Press the
[START]
key to begin running the test.
j. If the selected test included an excitation test, the following screen will be displayed:
CABLES ENERGIZED!
1500V 1.0A x1-x2
I = 0.6810 AMPS
V = 61.0 VAC
The “HIGH VOLTAGE PRESENT” light will be illuminated to indicate that high
voltage is present.
NOTE
k. If the selected test included a ratio test, the following screen will be displayed:
RATIO TEST
Vx = 39.9 Vh = 0.4984
I = 0.1324 RAT=+80.058
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When the testing is finished, the final results graph will be displayed:
Press any key on the keypad to continue.
l. The following screen will be displayed:
print test results?
1. YES
2. NO
EZCT S2A USER’S MANUAL REV 1
Press the [1] key (YES) if you would like to print the test results. The test results will be
printed on the thermal printer. A typical EZCT S2A tabulated test report printout is
shown in Figure 5. A typical graphic report is shown in Figure 6.
Press the [2] key (NO) if you do not want to print the test results.
m. The following screen will be displayed:
KEEP THIS TEST?
1. YES
2. NO
Press the
[1] key (YES) to keep the test results.
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n. The following screen will be displayed:
TEST 1 SAVED
Press any key to continue.
o. The following screen will be displayed:
RUN ANOTHER TEST?
1. YES
2. NO
Press the [2] key (NO).
p. The following screen will be displayed:
SAVE THIS RECORD?
1. YES
2. NO
Press the
[1] key (YES) to save the record.
The following screen will be displayed momentarily:
SAVING RECORD...
PLEASE WAIT...
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q. The following confirmation screen will then be displayed:
RECORD NUMBER 1
has been saved!
The test record number is automatically assigned to each test record stored in
the EZCT S2A’s Flash EEPROM.
NOTE
Press any key to return to the “START-UP” menu.
EZCT S2A USER’S MANUAL REV 1
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Figure 5. Typical EZCT S2A Tabulated Report Printout
EZCT S2A USER’S MANUAL REV 1
Table 3. Descriptions of Tabulated Test Results Elements
Item
Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
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Description
Test record header information.
The X terminals (taps) that were selected for this test.
Test note for this particular test. The test note can be up to 20-characters long.
Recorded excitation current readings on the CT secondary winding.
Recorded excitation test voltages applied to the CT secondary winding.
Impedance calculated at each data point.
The voltage, current, and impedance data points recorded on the graph grid-marks.
ASA 10/50 knee point voltage and excitation current
(This is equivalent to the IEC 10/50 and ANSI 10/50 knee point voltage and excitation current)
IEEE 30° knee point voltage and excitation current.
IEEE 45° knee point voltage and excitation current.
CT nameplate turns ratio.
Measured turns ratio.
Turns ratio percentage error.
Polarity of the CT.
Measured phase angle.
Excitation voltage used in CT turns ratio test.
Excitation current in turns ratio test.
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Knee Point Marker
Figure 6. Typical EZCT S2A Graphic Report
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EZCT S2A USER’S MANUAL REV 1
3.3 Working With Test Records
3.3.1. Restoring and Printing a Test Record From Flash EEPROM
You can restore a test record from the EZCT S2A’s Flash EEPROM to the working memory. You
can then print the restored test record on the unit’s built-in thermal printer. To restore a test
record:
a. Start from the “START-UP” menu:
1. RUN TEST 02/16/10
2. SETUP 10:24:25
3. TEST PLANS
4. DIAGNOSTIC
Press the
[2]
key (SETUP).
b. The following screen will be displayed:
1. RECORD ID
2. PRINT RECORD
3. RECORD DIRECTORY
4. SAVE/RES RECORD
5. ERASE RECORD
6. NEXT PAGE
Press the
[4]
key (SAVE/RES RECORD).
c. The following screen will be displayed:
RESTORE RECORD
1. enter record number
2. scroll to select
If you have a USB Flash drive inserted in the EZCT S2A’s “USB MEM” port, the
following screen will be displayed instead of the above screen:
NOTE
1. RESTORE RECORD
2. COPY TO THUMB DRIVE
Press the
[1]
key (RESTORE RECORD).
The following screen will be displayed:
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1. INTERNAL STORAGE
2. THUMB DRIVE
Press the [1] key (INTERNAL STORAGE).
The following screen will then be displayed:
RESTORE RECORD
1. enter record number
2. scroll to select
Continue with the steps below.
1. ENTER RECORD NUMBER
If you know the record number that you would like to restore, press the [1] key.
The following screen will be displayed:
RESTORE RECORD
NUMBER:
Type the record number using the alpha-numeric keypad and then press the
[ENTER] key. The test record’s graph will be displayed as shown below:
Press any key to continue.
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EZCT S2A USER’S MANUAL REV 1
The following screen will be displayed:
RECORD RESTORED!
PRINT RECORD?
1. YES
2. NO
If you do not want to print the test record, press the
[2] key (NO). The test record
will be restored to the working memory, and you will be returned to the “STARTUP” menu.
If you would like to print the test record, press the
[1] key (YES). Continue to step d.
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