Megger MVCT User Manual
  1. Manuals
  2. Brands
  3. Megger Manuals
  4. Test Equipment
  5. MVCT
  6. User manual
Megger MVCT User Manual

Megger MVCT User Manual

Voltage and current transformer test instrument
Hide thumbs
Table of Contents

Advertisement

Quick Links

Download this manual
MEGGER VOLTAGE AND CURRENT TRANSFORMER TEST
INSTRUMENT
MVCT USER MANUAL
May 8, 2020
Part#86027R5
1

Advertisement

Table of Contents
loading
Need help?

Need help?

Do you have a question about the MVCT and is the answer not in the manual?

Questions and answers

Related Manuals for Megger MVCT

Summary of Contents for Megger MVCT

  • Page 1 MEGGER VOLTAGE AND CURRENT TRANSFORMER TEST INSTRUMENT MVCT USER MANUAL May 8, 2020 Part#86027R5...

  • Page 2: Table Of Contents

    MVCT............................. 12 Introduction ............................12 Terminology ............................12 1.2.1 Acronyms ........................12 MVCT Unpack and Preparation for Use................13 Contents of MVCT kit ..........................13 Assembly and Installation ........................ 15 Communication Ports ........................15 2.3.1 Ethernet Ports on MVCT ..................... 15 2.3.2...
  • Page 3 Manual Test ............................118 Demagnetization ..........................121 Self Test ..............................123 Testing VT’s with MVCT ...................... 125 Running a Complete Test of VT and Test Plan Creation ........... 125 Testing VT Ratio and Phase ......................131 Testing Voltage Transformer – Saturation/Excitation Test ..........135 Testing Voltage Transformer Winding Resistance : ............
  • Page 4 List of Figures Figure 1 Ethernet Ports ....................... 16 Figure 2 Ethernet Port to Power Display ..................16 Figure 3 USB Port ......................... 16 Figure 4 Initial Screen ........................24 Figure 5 Instrument Connection Screen ..................25 Figure 6 Boot Up Home Screen ....................25 Figure 7 PowerDB Lite Initial Screen ..................
  • Page 5 Figure 47 VT Winding Resistance Test Screen ................75 Figure 48 Short Circuit Impedance Test Screen ................76 Figure 49 Sample VT Test Report ....................77 Figure 50 Testing - File Operation Tool Bar ................78 Figure 51 VT Testing: File Manager Screen ................79 Figure 52 VT Testing: File Save from PC ..................
  • Page 6 Figure 93 CT Demagnetization Connection Diagram ..............122 Figure 94 CT Demagnetizing Process Screen ................123 Figure 95 CT Self Diagnostic Connection Diagram ..............124 Figure 96 CT Self Diagnostic Test Screen ................. 125 Figure 97 VT Test Plan Screen ....................126 Figure 98 VT Connection Diagram for Winding Resistance ............
  • Page 7 Megger. Megger, the Megger logo are trademarks of Megger. All other trademarks are the property of their respective owners.
  • Page 8 SAFETY PRECAUTIONS WARNING: VOLTAGES GENERATED BY THIS INSTRUMENT CAN BE HAZARDOUS This instrument has been designed for operator safety; however, no design can completely protect against incorrect use. Electrical circuits are dangerous and can be lethal when lack of caution and poor safety practices are used. There are several standard safety precautions that should be taken by the operator.
  • Page 9 The purpose of this equipment is limited to use as described in this instruction manual. Should a situation arise that is not covered in the general or specific safety precaution please contact Megger regional representative or Megger, Dallas Texas.
  • Page 10 WEEE The crossed out wheeled bin placed on Megger products is a reminder not to dispose of the product at the end of its life with general waste. Megger is registered in the UK as a Producer of Electrical and Electronic Equipment. The Registration No...
  • Page 11 Megger...

  • Page 12: Mvct

    CT’s and perform all tests – saturation, ratio and polarity, winding resistance, and insulation – on all taps with the push of a button and without changing leads. The MVCT can be controlled via an integrated large, full color, high resolution, TFT LCD touch screen which allows the user to perform manual and automatic testing quickly and easily using the manual test screens, as well as using pre- constructed test routines.

  • Page 13: Mvct Unpack And Preparation For Use

    Contents within the shipping container will vary depending upon how the MVCT was configured. Below is a complete list of all accessories available with the MVCT. Please check the order and the configuration of your MVCT to confirm which accessories should be included with your instrument.
  • Page 14 Megger of any shortages. Telephone 1-800-723 2861 and ask for Dallas customer service department. Again if damage received in transit is discovered, file a claim with the carrier at once and notify Megger or its nearest authorized sales representative, giving a detailed description of the damage.

  • Page 15: Assembly And Installation

    On the MVCT this port is labeled STVI. This port contains the PoE power supply, and will provide power to either the display or an STVI. The IN port on the MVCT may be used to interconnect multiple SMRT units together for synchronous multi-phase operation.. The third Ethernet port label PC is the...

  • Page 16: Ethernet Ports On Display

    2.3.3 USB 2.0 Interface on Display There is one USB 2.0 Interface port on the MVCT display unit mounted in the lid. This port is used for upgrading firmware to the MVCT unit, or upgrading the PowerDB software using a USB Memory Stick. It may also be used in conjunction with a USB mouse for ease of manual control, even a USB wireless mouse maybe used with the display.

  • Page 17: Operating System

    General The purpose of this section is to explain the basic theory of the following tests and to guide the operator for making appropriate measurements with the MVCT. The following tests can be performed by the MVCT. 3.2 CT Testing 3.2.1...

  • Page 18: Polarity Test

    The MVCT performs the ratio test by either selecting Ratio test in the Run All test configuration or using the ratio test screen. User can also select manual Ratio test by selecting manual option and controlling the secondary applied voltage.
  • Page 19 A CT with reverse polarity would read the sum of the two primary and secondary voltages indicating a phase difference of approximately 180 degrees. MVCT performs this test in automated fashion and display the result as either Polarity correct or incorrect.

  • Page 20: Excitation Test

    CT is increased slowly automatically by the test set. Voltage and current readings for the secondary winding of CT are stored in the internal memory. At 300V AC the MVCT will switch to DC voltage to finish saturating the CT. Test set automatically convert the DC voltage readings, generate an AC excitation curve and determines the “Knee”...

  • Page 21: Insulation Resistance Test

    CT curves. The MVCT plots the saturation curve on the display screen. Once a knee point is determined by the test set, it will also display the corresponding saturation voltage and saturation current on the display screen.

  • Page 22: Burden Test

    over a period of time. A sharp dip in trending of insulation resistance values, point towards insulation degradation and further investigation is warranted to diagnose the problem. 3.2.5 Burden Test Burden can be defined as the total impedance in ohms on the CT output terminals. Each CT has a secondary burden when connected in a relay or metering circuit.

  • Page 23: Secondary Winding Resistance

    Initial Start Up 1. If the unit was ordered with an integrated display, using the Ethernet cable supplied with the unit connect the STVI Ethernet Port on the MVCT unit to the Ethernet port on the lower front of the display module 2.

  • Page 24: User Interface

    Integrated Display or Smart Touch View Interface Depending on how the unit was ordered, the MVCT can be controlled using the integrated display, or a personal computer using PowerDB Lite software. Both of these methods of control will have the same user interface in the software and this will be outlined throughout.

  • Page 25: Personal Computer Interface

    Figure 5 Instrument Connection Screen The user should select the connection icon in the top left conner to connect to the MVCT. The user will then be brought to the “Home Screen”. If the MVCT has an integrated display, after powering up the MVCT, the user will be brought to the “Homes Screen”...

  • Page 26: Figure 7 Powerdb Lite Initial Screen

    From the PowerDB Lite Initial screen the user can control many of Megger’s different testing instruments. After connecting the PC to the MVCT using the supplied Ethernet cable, to log onto the MVCT the user needs to select the MVCT icon. This will launch the Instrument Configuration dialog as...

  • Page 27: Figure 8 Instrument Configuration Dialog

    Here the user may select the appropriate form for the type of testing to be performed. For testing Instrument Transformers, the MVCT Form should be selected and then click OK on the dialog. This will bring the user to the instrument log on screen.

  • Page 28: Figure 10 Instrument Logon Screen

    Figure 11 Connection Dialog Once the PC has begun communicating with the MVCT, the device will appear in the dialog while showing the units serial number and the time since the unit was turned on. To complete the logon process select the unit.

  • Page 29: Software Interface

    Figure 12 PowerDB Lite Home Screen Software Interface Whether the MVCT is being controlled with an integrated display, an STVI, or a personal computer the software has the same user interface. From this Home screen the user can navigate to the desired test screen.
  • Page 30 CT Testing Selection VT Testing Selection Relay Testing Selection The following operations are available when the MVCT is in CT testing mode Run All Test s Manual Test Demagnetization “Self Diagnostic” Saturation Test Ratio Test Winding Resistance Test Insulation Test...
  • Page 31 The following operations are available when the MVCT is in Basic VT testing mode Run All Tests Demagnetization “Self Diagnostic” VT Ratio Test VT Secondary Winding Resistance Test Additional operations available when the MRCT is in Advanced VT testing mode...

  • Page 32: Testing Mode

    5.4.1 CT Testing Mode – Menu Items Menu items are considered either system wide menu items or menu items that are available only within a specific mode of testing. Below are all the menu items available when the MVCT is set up for test CT’s 5.4.1.1...

  • Page 33: Figure 13 Device Settings - Ct Testing

    Figure 13 Device Settings – CT Testing Within this screen all device settings are visible. However, only the settings that apply to the current mode of testing will be accessible. By selecting the appropriate button, the user can:  Saturation Standard: Select between ANSI 45, ANSI 30, IEC 60044-1, IEC6044-6, or IEC61869 ...
  • Page 34 The MVCT uses both AS and DC voltage for testing saturation point and knee points of CT. The MVCT has the ability to output up to 300V AC. This functionality allows the user to select the method which the MVCT uses for both saturating and/or demagnetizing a CT.
  • Page 35 Then insert the USB stick into the USB port of the MVCT and hit the Set Logos button. This will copy and store the file and the logo will be included on top of the report in the future ...

  • Page 36: Figure 14 Name Plate Data - Ct Testing Mode

    Number of CTs: If controlling MVCT with Megger STVI then pp to 12 CT can be included within one report. If controlling MVCT with PowerDB installed on PC then up to 18 CT can be included in one report. ...
  • Page 37 30V. So in order to gather enough data points to calculate the knee point, if the type of CT is set to “Metering” the MVCT will increment the voltage during the excitation by ½ V increments. Conversely a relaying/protection class CT will saturate at much higher voltage levels.

  • Page 38: Figure 15 Home Screen Ct Testing

    Note: All the information in Nameplate screen is optional. It is not required to perform a test on CT. The MVCT will attempt to estimate the nameplate values. However by inputting any data that is known a more precise estimate can be made for any missing data and a more complete report can be generated.

  • Page 39: Figure 16 Run All Test Screen

    5.4.1.5 Run All Tests Selection of Run All Tests button will bring the user to the Test Configuration screen Figure 16 Run All Test Screen The user can easily configure a test plan for a current transformer by checking the box adjacent to the desired test of the desired tap.

  • Page 40: Figure 17 Manual Test Screen

    CT. Current Injection: If the MVCT has been ordered with the “Relay Testing” option then the Manual Current Injection screen will be available. To inject current into any load, the user must enter the...
  • Page 41 Then selecting the ON button on the touch screen the MVCT will first display a connection diagram. Once the user verifies the connection, by selecting the blue play button the MVCT will output the specified current level Ratio Testing; To manually test the ratio of a CT the user is required to first select which individual tap...

  • Page 42: Figure 18 Manual Test Connection Diagram

    Figure 18 Manual Test Connection Diagram After the MVCT has begun to inject voltage, the voltage and current readings will be displayed along with the calculated ratio. In order to ensure accurate results on the ratio, the voltage should be ramped to a level of at least 10% of the value of the knee point of the CT.
  • Page 43 Hitting the select tap button will activate the tap selection dialog After selection of the desired individual tap selection, the user may adjust the voltage increment selecting the Ramp adjustment button This will activate the ramp parameter dialog allowing the user may select the amount of increment the voltgae is either decreased ir increased by turning the knob on the STVI or the up/down arrow keys on a laptop After the desired tap selection is made and any adjustments made to the ramp parameter, the user...

  • Page 44: Figure 19 Manual Test Example

    Figure 19 Manual Test Example Once the user has generated at least two data points, the MVCT will begin to graph the saturation curve. The user can then continue to ramp the voltage while taking data points until the CT reaches saturation.

  • Page 45: Figure 20 Demagnetization Connection Diagram

    5.4.1.7 Demagnetization Selection of Demagnetization, brings the user to the following connection diagram . Figure 20 Demagnetization Connection Diagram After confirming the connections are correct, continue with demagnetizing the CT by selecting the green CHECK. The red X will cancel the operation. After selecting to continue the operation, the user will be advised that the CT is being demagnetized...

  • Page 46: Figure 21 Demagnetization Process

    Figure 21 Demagnetization Process Upon completion, the user will be returned to the Main Test Configure Screen and notified the demagnetization process is complete. 5.4.1.8 Self Test Selection of the “Self Diagnostic” navigation button from the home screen will display a connection diagram...

  • Page 47: Figure 22 Self Test Connection Diagram

    Figure 22 Self Test Connection Diagram After the user has ensured the MVCT is connected properly as in the diagram, the self test is begun by selecting the blue play button While the user can completely test a current transformer from the Run All Tests screen, individual tests amy be accessed from the correlating buttons in the drop down list.

  • Page 48: Figure 23 Saturation Test Screen

    Figure 23 Saturation Test Screen Within this screen the user can select between Concurrent and Non concurrent Testing When Concurrent Mode of testing is selected, the user is required to select how many taps is desired to test simultaneously However if the Non Concurrent Mode of testing is selected, the user is required to select which individual tap is desired Hitting the select tap button will activate the tap selection dialog...

  • Page 49: Figure 24 Ratio Test Screen

    After either selecting the number of taps or the individual tap selection, the saturation test is begun by selecting the blue play button. 5.4.1.10 Ratio Selection of Ratio Test button from the test configuration screen will bring the user to the following Ratio Test screen Figure 24 Ratio Test Screen Within this screen the user can select between Concurrent and Non concurrent Testing...
  • Page 50 When Concurrent Mode of testing is selected, the user is required to select how many taps is desired to test simultaneously However if the Non Concurrent Mode of testing is selected, the user is required to select which individual tap is desired Hitting the select tap button will activate the tap selection dialog After either selecting the number of taps or the individual tap selection, the ratio test is begun by selecting the blue play button.

  • Page 51: Figure 25 Winding Resistance Test Screen

    Selection of Winding Resistance Test button from the test configuration screen will bring the user to the following Winding Resistance Test screen. Figure 25 Winding Resistance Test Screen Use the Zero Leads button to zero out the leads from the measurement. This will ensure no resistance from the leads is included in the resistance measurement and improve the accuracy of the measurement.
  • Page 52 However if the Non Concurrent Mode of testing is selected, the user is required to select which individual tap is desired Hitting the select tap button will activate the tap selection dialog After either selecting the number of taps or the individual tap selection, the Winding Resistance test is begun by selecting the blue play button.

  • Page 53: Figure 26 Insulation Resistance Test Screen

    Figure 26 Insulation Resistance Test Screen Within the Insulation test screen, the user may select the desired test level of either 500V or 1 KV by using the Voltage selection button Each test may be set to a different test voltage. The user can also set the same test voltage to all tests by selecting the all Ranges Button And then selecting the desired voltage After selecting the desired test voltage, the user may select which test is desired by checking the...

  • Page 54: Figure 27 Burden Test Screen

    Then after selecting both the desired test voltage and the desired test, the insulation testing is begun by selecting the blue play button. 5.4.1.13 Burden Selection of Burden Test button from the test configuration screen will bring the user to the following Burden Test screen Figure 27 Burden Test Screen Within the Burden test screen, the user may select the appropriate test current of either...

  • Page 55: Figure 28 Sample Ct Test Report

    After either selecting the appropriate test current, the burden test is begun by selecting the blue play button. 5.4.1.14 View Report If a test has been run and data is present the View Test Report button will be available. Selection of this button will generate a report of all test data for the active CTs. Data in the report regarding customer information may be entered here Figure 28 Sample CT Test Report...
  • Page 56 5.4.1.15 Delete Data If a test has been ran and data is present; the Delete Test Data button will be available. Selection of this button activates the following dialog This will allow the user three options of deleting data  Clear test data on screen will only clear the data of the test screen currently active ...

  • Page 57: Figure 29 Sample Multi Tap Test Report

    Figure 29 Sample Multi Tap Test Report The MVCT will provide a concise one page report that will include all testing results including the data from the following tests: excitation; ratio; phase deviation; polarity; winding resistance; and insulation resistance. The MVCT report can also be configured to provide additional data including the ratio and...

  • Page 58: Figure 30 Ratio And Phase Error Tables

    Figure 30 Ratio and Phase Error Tables In device settings the user can configure the report to contain any of the following: Ratio Error Table, Ratio Error Graph, Phase Displacement Table, Phase Displacement Graph and assessment of the CT under test. If any of these have been included in the report, after testing the CT, the user can use the Ratio Phase Error Button to control the number of taps displayed.

  • Page 59: Figure 31 Report Tap Configuration Dialog

    Then the “ Ratio & Phase Error “ button will be visible within the report. This button will give the user additional control over what is contained within the report. If the user included any of the following in the report: Ratio Error Table, Ratio Error Graph, Phase Displacement Table, Phase Displacement Graph and the CT under test has more than 1 ratio, then the user can specify to include additional taps in the report Figure 31 Report Tap Configuration Dialog...

  • Page 60: Figure 33 Excitation Curve Data

    Additional data points can be viewed from the Saturation/Excitation Test Screen. Figure 32 Excitation Curve Data Within the test screen, if the test has completed and data is available, the user can access this data by selecting the “ View Data” button. Selection of the view data button will launch a data viewer that will allow the user to view, or copy the data for inclusion into a separate file that can be included with the standard CT Test Report.

  • Page 61: Figure 34 View Excitation Data Points

    5.4.1.18 File Operations Files operations will vary depending upon whether the user is controlling the MVCT with a PowerDB installed on PC or the MVCT’s integrated display. For units being controlled with the MVCT’s integrated display, once a CT has been tested and a test file exists, the File Manager button will be available.

  • Page 62: Figure 36 File Manager Screen

    Figure 35 File Manager Screen File manager screen is used to view and access the stored test results. All stored test results are displayed in alphabetical order along with date and time stampings. Function buttons are used to recall, delete or transfer the test results. The function buttons are used to manage files as below: Used to open file highlighted in the internal storage list Used to save file named in edit box to system memory...

  • Page 63: Figure 37 File Operations Using Pc

    Cancels operation and closes dialog Used to scroll file selection highlight up and down If the MVCT is being controlled using PowerDb installed on a PC, then a different interface is available for file operations. Figure 36 File Operations Using PC...

  • Page 64: Vt Testing Mode - Menu Items

    VT Testing Mode – Menu Items Menu items are considered either system wide menu items or menu item that are available only within a specific mode of testing. Below are all the menu items available when the MVCT is set up for test VT’s 5.4.2.1...
  • Page 65 Allows the user to enable and disable the lead checking algorithms. If enabled the MVCT will check connections prior to a test and monitor voltages and currents during the test. Anytime an unexpected value is detected the user will be warned to check the connections.
  • Page 66 Then insert the USB stick into the USB port of the MVCT and hit the Set Logos button. This will copy and store the file and the logo will be included on top of the report in the future ...

  • Page 67: Figure 40 Name Plate Data - Vt Testing Mode

    Can be used to identify the phase that the VT is located on  Metering or Relaying: Select the type of VT. Depending upon the type of VT selected, the MVCT will populate the accuracy class selection field with the appropriate classes ...
  • Page 68 Home Screen Within the “Home Screen “ selecting the VT TEST button will cause the button to turn bright yellow. This will inform the user that the MVCT is now in VT Testing mode. From here the user will have access...

  • Page 69: Figure 41 Home Screen Vt Testing Mode

    VT testing. With Basic VT Testing, the Ratio/Phase Error test and the Winding resistance test is available. If the MVCT if configured for Advanced VT Testing, in addition to the tests available in Basic, the MVCT will also have the Excitation/Saturation test, and the Short Circuit Impedance Test.

  • Page 70: Figure 42 Run All Test Screen

    Figure 41 Run All Test Screen In order for the MVCT to estimate the performance of the VT, the MVCT must have the Advanced VT package installed and each test outlined in the Run All test screen must be performed on the VT. In the Basic VT testing the Saturation Test and Short Circuit Impedance Test are not available.

  • Page 71: Figure 43 Demagnetization Connection Diagram

    Used to auto select Winding Resistance Test on all windings Used to auto select Secondary Short Circuit Impedance test on all windings 5.4.2.6 Demagnetization Selection of Demagnetization, brings the user to the following connection diagram . Figure 42 Demagnetization Connection Diagram After confirming the connections are correct, continue with demagnetizing the VT by selecting the blue play button.

  • Page 72: Self Test

    Figure 43 Demagnetization Process Upon completion, the user will be returned to the Main Test Configure Screen and notified the demagnetization process is complete. 5.4.2.7 Self Test Selection of the “Self Diagnostic” navigation button from the home screen will display a connection diagram...

  • Page 73: Figure 45 Vt Ratio Test Screen

    After the user has ensured the MVCT is connected properly as in the diagram, the self test is begun by selecting the blue play button 5.4.2.8 Ratio Selection of Ratio Test button from the test configuration screen will bring the user to the...

  • Page 74: Figure 46 Saturation Test Screen

    5.4.2.9 Saturation Selection of Saturation Test button from the test configuration screen will bring the user to the following Saturation Test screen Figure 45 Saturation Test Screen The Saturation test is begun by selecting the Blue Play button 5.4.2.10 Winding Resistance...
  • Page 75 Selection of Winding Resistance Test button from the test configuration screen will bring the user to the following Winding Resistance Test screen. Figure 46 VT Winding Resistance Test Screen Use the Zero Leads button to zero out the leads from the measurement. This will ensure no resistance from the leads is included in the resistance measurement and improve the accuracy of the measurement.
  • Page 76 Selection of Impedance Test button from the test configuration screen will bring the user to the following Secondary Short Circuit Impedance Test screen. Figure 47 Short Circuit Impedance Test Screen The Short Circuit Impedance is begun by selecting the Blue Play button...
  • Page 77 5.4.2.12 View Report If a test has been completed and data is present the View Test Report button will be available. Selection of this button will generate a report of all test data for the active VTs. Data in the report regarding customer information may be entered here.
  • Page 78 5.4.2.14 Report Configuration The MVCT will provide a concise one page report that will include all testing results. With the Basic VT Testing Option the report will include the data from the following tests: ratio; phase deviation; polarity; winding resistance. If the MVCT has the Advanced VT Option, in addition to the data from the previous tests, the report will also include testing data from the excitation/saturation test, and the short circuit impedance test.
  • Page 79 Figure 50 VT Testing: File Manager Screen File manager screen is used to view and access the stored test results. All stored test results are displayed in alphabetical order along with date and time stampings. Function buttons are used to recall, delete or transfer the test results. The function buttons are used to manage files as below: Used to open file highlighted in the internal storage list Used to save file named in edit box to system memory...
  • Page 80 Cancels operation and closes dialog Used to scroll file selection highlight up and down If the MVCT is being controlled using PowerDb installed on a PC, then a different interface is available for file operations. Access to the file operations is gained through the FILE tab in the PowerDB window.

  • Page 81: Relay Testing Mode

    Selection of the Relay testing mode will bring the user to a new system Log on screen Figure 52 Relay Testing System Log On Selection of the network button in the top left corner of the window will log the user onto the MVCT’s relay testing mode of operation.

  • Page 82: Testing Ct With Mvct

    2 connectors to properly align them before connecting. On test lead set labeled CT H/P Connect the high voltage connector color coded blue to the MVCT high voltage connector that is color coded blue and labeled MEASUREMEMT. Use the red...
  • Page 83 H1 and H2.Observe the polarity marks on the CT (H1 on the test set is polarity terminal). WARNING The MVCT produces high voltages and currents during the performance of tests. DO NOT TOUCH connector clips or test leads while the MVCT is performing a test. 7. Turn Power ON/OFF switch to ON 8.
  • Page 84 Select the individual taps for saturation testing by placing a check in the corresponding box. Or select all taps by selecting the button. This will place a check corresponding to all taps. Select the individual taps for ratio testing by placing a check in the corresponding box.
  • Page 85 A connection diagram will appear showing how to properly connect the MVCT to the CT Figure 56 CT Connection Diagram Multi Tap: Concurrent Continue the test by selecting the Blue Play button At any point of time Test can be terminated by hitting the ABORT button at the top of any testing screen.

  • Page 86: Ct Saturation Test

    Ground each terminal to be tested with a safety ground stick, before making connections. 3. On test lead set labeled CT X/S connect the high voltage connector color coded green to the MVCT high voltage connector that is color coded green and labeled SOURCE Voltage.
  • Page 87 4. On test lead set labeled CT H/P Connect the high voltage connector color coded blue to the MVCT high voltage connector that is color coded blue and labeled MEASUREMEMT. Use the red alignment mark on the 2 connectors to properly align them before connecting 5.
  • Page 88 Figure 59 CT Saturation Test Screen - Concurrent Select the play button and a connection diagram will appear showing the proper connections for the MVCT to the CT Figure 60 CT Saturation Connection Diagram - Concurrent Check all connections to ensure correctness...
  • Page 89  X Voltage (V): The MVCT displays the real time voltage readings of the secondary X winding while the test is in progress.  X Current (A): The MVCT the real time current readings for the secondary X winding while the test is in progress.

  • Page 90: Method 2 - Non Concurrent Or Testing A Single Tap

    Ground each terminal to be tested with a safety ground stick, before making connections. On test lead set labeled CT X/S connect the high voltage connector color coded green to the MVCT high voltage connector that is color coded green and labeled SOURCE Voltage.
  • Page 91 4. On test lead set labeled CT H/P Connect the high voltage connector color coded blue to the MVCT high voltage connector that is color coded blue and labeled MEASUREMEMT. Use the red alignment mark on the 2 connectors to properly align them before connecting 5.
  • Page 92 After selecting the appropriate tap, select the play button and a connection diagram will appear showing how to correctly connect the MVCT to the CT Figure 64 CT Saturation Connection Diagram - Non Concurrent...
  • Page 93 Check all connections to ensure correctness Hit Blue Play button to begin test.  The saturation will begin. X Voltage (V): The MVCT displays the real time voltage readings of the secondary X winding while the test is in progress.

  • Page 94: Ratio Test

    Ground each terminal to be tested with a safety ground stick, before making connections. 3. On test lead set labeled CT X/S connect the high voltage connector color coded green to the MVCT high voltage connector that is color coded green and labeled SOURCE Voltage.
  • Page 95 11 In the Ratio test screen, selecting the Concurrent Mode of operation will allow the user to test multiple taps in parallel. Figure 66 CT Ratio Test Screen – Concurrent 12 Select the play button and a connection diagram will appear showing the proper connections for the MVCT to the CT...
  • Page 96 Figure 67 CT Ratio Connection Diagram - Concurrent Check all connections to ensure correctness Hit Blue Play button A dialog will appear requesting how much Voltage to apply to the CT during the ratio test Enter a voltage 1V and 300V that is less than the knee point of the CT Hit Blue Play button to begin test.
  • Page 97 X Current (A): The MVCT the real time current readings for the secondary X winding while the  test is in progress. H Voltage (V): The MVCT the real time voltage readings of the primary H winding while the test  is in progress.

  • Page 98: Method 2 - Non Concurrent Or Testing A Single Tap

    Figure 69 CT Ratio Test Results - Concurrent Polarity: Unit automatically determines the polarity connections and displays the result as either polarity Correct or Incorrect. The phase angle deviation between the secondary and primary voltage is also displayed along with polarity. The ratio is defined as the number of turns in the secondary as compared to the number of turns in the primary.
  • Page 99 2 connectors to properly align them before connecting 4. On test lead set labeled CT H/P Connect the high voltage connector color coded blue to the MVCT high voltage connector that is color coded blue and labeled MEASUREMEMT. Use the red alignment mark on the 2 connectors to properly align them before connecting 5.
  • Page 100 Figure 70 CT Ratio Test Screen – Non Concurrent Hit the Select Tap function button to select the appropriate tap to be tested 11. Select the tap configuration before hitting the PLAY button. If PLAY button is pressed before selecting the tap, following message will appear:...
  • Page 101 After selecting the appropriate tap, select the play button and a connection diagram will appear showing how to correctly connect the MVCT to the CT Figure 71 CT Ratio Test Connection Diagram - Non Concurrent Check all connections to ensure correctness Hit Blue Play button.
  • Page 102 X Current (A): The MVCT the real time current readings for the secondary X winding while the test is in progress. H Voltage (V): The MVCT the real time voltage readings of the primary H winding while the test is in progress.

  • Page 103: Ct Winding Resistance Test

    Figure 73 CT Ratio Test Results – Non Concurrent Polarity: Unit automatically determines the polarity connections and displays the result as either polarity Correct or Incorrect. The phase angle deviation between the secondary and primary voltage is also displayed along with polarity. The ratio is defined as the number of turns in the secondary as compared to the number of turns in the primary.
  • Page 104 3. On test lead set labeled CT X/S connect the high voltage connector color coded green to the MVCT high voltage connector that is color coded green and labeled SOURCE Voltage. Use the red alignment marks on the 2 connectors to properly align them before connecting 4.
  • Page 105 Figure 74 CT Winding Test Screen – Concurrent Select the play button and a connection diagram will appear showing the proper connections for the MVCT to the CT Figure 75 CT Winding Connection Diagram – Concurrent Check all connections to ensure correctness...
  • Page 106  Voltage (V): The MVCT displays the real time voltage readings of the secondary winding while the test is in progress.  Current (A): The MVCT the real time current readings for the secondary winding while the test is in progress.

  • Page 107: Method 2 - Non Concurrent Or Testing A Single Tap

    Figure 77 CT Winding Results - Concurrent Winding resistance test is used to determine if the dc resistance of the CT secondary winding is within specification or not. A DC current is applied and voltage is measured to determine the winding resistance for the selected tap.
  • Page 108 2 connectors to properly align them before connecting 4. On test lead set labeled CT H/P Connect the high voltage connector color coded blue to the MVCT high voltage connector that is color coded blue and labeled MEASUREMEMT. Use the red alignment mark on the 2 connectors to properly align them before connecting 5.
  • Page 109 After selecting the appropriate tap, select the play button and a connection diagram will appear showing how to correctly connect the MVCT to the CT Figure 79 CT Winding Resistance Connection Diagram Non Concurrent Check all connections to ensure correctness Hit Blue Play button to begin test.
  • Page 110  while the test is in progress.  X Current (A): The MVCT the real time DC current readings for the secondary X winding while the test is in progress. 15. At any point of time Test can be terminated by hitting the ABORT button at the top of the screen...

  • Page 111: Insulation Test

    2 connectors to properly align them before connecting 4. On test lead set labeled CT H/P Connect the high voltage connector color coded blue to the MVCT high voltage connector that is color coded blue and labeled MEASUREMEMT. Use the red alignment mark on the 2 connectors to properly align them before connecting 5.
  • Page 112 Primary to Secondary b) Primary to Ground c) Secondary to Ground Select the play button and a connection diagram will appear showing how to correctly connect the MVCT to the CT...
  • Page 113 Figure 83 CT Insulation Test Connection Diagram Check all connections to ensure correctness 13. Hit Blue Play button to begin test. 14. At any point of time Test can be terminated by hitting the ABORT button at the top of the screen. Figure 84 CT Insulation Testing Screen...

  • Page 114: Burden Test

    Connect the test set primary binding posts H1 and H2 to either side of the CT burden. and H2. 5. On test lead set labeled CT X/S connect the high voltage connector color coded green to the MVCT high voltage connector that is color coded green and labeled SOURCE Voltage.
  • Page 115 H1 and H2.Observe the polarity marks on the CT (H1 on the test set is polarity terminal). WARNING The MVCT produces high voltages and currents during the performance of tests. DO NOT TOUCH connector clips or test leads while the MVCT is performing a test.
  • Page 116 Hit Blue Play button to begin test. The Burden test will begin. Voltage (V): The MVCT displays the real time voltage readings of the burden while the test is in progress. Current (A): The MVCT the real time current readings for the burden while the test is in progress.
  • Page 117 Figure 88 CT Burden Test Abort 18. Upon completion of all tests the results will be displayed in the test screen or in a test report. Figure 89 CT Burden Test Results Screen Burden test is performed to verify that CT under test is capable of supplying a known current into a know burden while maintaining its stated accuracy.

  • Page 118: Manual Test

    Ground each terminal to be tested with a safety ground stick, before making connections. 3. On test lead set labeled CT X/S connect the high voltage connector color coded green to the MVCT high voltage connector that is color coded green and labeled SOURCE Voltage.
  • Page 119 Figure 90 CT Manual Test Screen 9. In the Manual Test screen, by selecting the Ramp adjustment button , the user may select the amount of increment the voltgae is either decreased ir increased by turning the knob on the STVI. 10.
  • Page 120 Figure 91 CT Manual Test Connection Diagram 12. Ensure the MVCT is properly connected. 13. Begin the test by selecting the Blue play button. 14. The MVCT will display: Secondary (X) Voltage: The applied secondary test voltage is displayed on the screen in digital readout form.

  • Page 121: Demagnetization

    On test lead set labeled CT H/P Connect the high voltage connector color coded blue to the MVCT high voltage connector that is color coded blue and labeled MEASUREMEMT. Use the red alignment mark on the 2 connectors to properly align them before connecting On test lead set labeled CT X/S connect the test lead binding posts X1 and X5 to secondary of the current transformer on the desired tap.
  • Page 122 Figure 92 CT Demagnetization Connection Diagram 10 Confirming all the connections are correct, 11 Continue with demagnetizing the CT by selecting the Blue Play button CHECK. The red X will cancel the operation. 12 After selecting to continue the operation, the user will be advised that the CT is being demagnetized...

  • Page 123: Self Test

    Use the red alignment marks on the 2 connectors to properly align them before connecting. 4. On test lead set labeled CT H/P Connect the high voltage connector color coded blue to the MVCT high voltage connector that is color coded blue and labeled MEASUREMEMT. Use the red alignment mark on the 2 connectors to properly align them before connecting 5.
  • Page 124 WARNING The MVCT produces high voltages and currents during the performance of tests. DO NOT TOUCH connector clips or test leads while the MVCT is performing a test. 6. Turn Power ON/OFF switch to ON. After the boot up, in the Home Screen select the “Self Diagnostic” button The following connection diagram will appear.

  • Page 125: Testing Vt's With Mvct

    9. After the unit has checked the voltage and current generators and meters are working properly, the user will be advised the unit has passed or failed the test 7.0 Testing VT’s with MVCT Running a Complete Test of VT and Test Plan Creation Refer to the safety instructions first before use of the equipment.
  • Page 126 WARNING The MVCT produces high voltages and currents during the performance of tests. DO NOT TOUCH connector clips or test leads while the MVCT is performing a test. 3. Turn Power ON/OFF switch to ON. 4. After the boot up, set the testing mode to VT and select the “Nameplate Information” menu by selecting Name Plate navigation button.
  • Page 127 At this point, this test file could be saved, opened at a later date , and ran. It can also be ran at this time by selecting the Blue Play button A connection diagram will appear showing how to properly connect the MVCT to the VT...
  • Page 128 At any point of time Test can be terminated by hitting the ABORT button at the top of any testing screen. Figure 98 VT Winding Resistance Abort Upon completion of Winding Resistance Test, the MVCT will automatically demagnetize the VT...
  • Page 129 Upon completion of demagnetization the MVCT will then perform an excitation/saturation test on the VT Figure 100 VT Saturation/Excitation Test Upon completion of the excitation test, the MVCT will stop and display a connection diagram for the Secondary Short Circuit Impedance test...
  • Page 130 Follow the connection diagram and ensure the MVCT is properly connected for this test. Select the Blue Play Button to continue the test After completion of the Impedance test, the MVCT will display the connection diagram for the Ratio Test...

  • Page 131: Testing Vt Ratio And Phase

    Select the Blue Play Button to continue the test After completion of the ratio test, the MVCT will take all the measurements and build a test report. This test report will be automatically displayed. Figure 103 Sample VT Test Report 7.2 Testing VT Ratio and Phase...
  • Page 132 TOUCH connector clips or test leads while the MVCT is performing a test. Turn Power ON/OFF switch to ON. After the boot up, put the MVCT in VT Testing Mode by selecting the VT button at the top of the home screen.
  • Page 133 Figure 104 VT Ratio Test Screen 11 , Select the play button and a connection diagram will appear showing how to correctly connect the MVCT to the VT Figure 105 VT Ratio Test Connection Diagram 12 Check all connections to ensure correctness...
  • Page 134 Hit Blue Play button to begin test 15 The Ratio test will begin. H Current (A): The MVCT the real time current readings for the primary H winding while the test is in progress. H Voltage (V): The MVCT displays the real time voltage readings of the primary H winding while the test is in progress.

  • Page 135: Testing Voltage Transformer - Saturation/Excitation Test

    Figure 107 VT Ratio Test Results Testing Voltage Transformer – Saturation/Excitation Test Refer to the safety instructions first before use of the equipment. 1. Verify the Power ON/OFF switch is OFF. Power the test set from a suitable source of power (95-125 or 195-265 V50/60 Hz). Connect the ground wing nut to a suitable ground WARNING There is always the possibility of voltages being induced at the terminals of a test...
  • Page 136 WARNING The MVCT produces high voltages and currents during the performance of tests. DO NOT TOUCH connector clips or test leads while the MVCT is performing a test. Turn Power ON/OFF switch to ON. After the boot up, in the Home Screen, select the VT button at the top of the screen to put the MVCT in voltage transformer testing mode.
  • Page 137 Hit Blue Play button to begin test. The saturation will begin and the test voltage and current will be displayed  X Current (A): The MVCT the real time current readings for the secondary winding while the test is in progress.

  • Page 138: Testing Voltage Transformer Winding Resistance

    Ground each terminal to be tested with a safety ground stick, before making connections. 3. On test lead set labeled VT H/P connect the high voltage connector color coded green to the MVCT high voltage connector that is color coded green and labeled SOURCE Voltage. Use the...
  • Page 139 MVCT is performing a test. 7. Turn Power ON/OFF switch to ON After boot up, in the Home Screen set the MVCT to VT Testing mode and select the “Winding Resistance Test” button.
  • Page 140  while the test is in progress.  X Current (A): The MVCT the real time DC current readings for the secondary X winding while the test is in progress. 13. At any point of time Test can be terminated by hitting the ABORT button at the top...

  • Page 141: Testing Voltage Transformer: Secondary Short Circuit Impedance

    Figure 113 VT Winding Test Screen –Abort 14. Upon completion of all tests the results will be displayed in the test screen or in a test report. Figure 114 VT Winding Results Testing Voltage Transformer: Secondary Short Circuit Impedance Refer to the safety instructions first before use of the equipment.
  • Page 142 TOUCH connector clips or test leads while the MVCT is performing a test. Turn Power ON/OFF switch to ON. After boot up, in the Home Screen put the MVCT in voltage transformer testing mode by selecting the VT button. Select the “Secondary Short Circuit Impedance” button In the VT section of the Home Screen. This...
  • Page 143 8. Hit Blue Play button to begin test. The Short Circuit Impedance test will begin.  X Current (A): The MVCT the real time DC current readings for the secondary X winding while the test is in progress. Voltage (V): The MVCT displays the real time voltage readings of the secondary X winding while ...
  • Page 144 Figure 117 VT Short Circuit Impedance –Abort 11. Upon completion of test the results will be displayed in the test screen or in a test report if desired. Figure 118 VT Short Circuit Impedance Results Short Circuit Impedance test is used to determine the impedance of the VT secondary and primary windings.

  • Page 145: Testing Voltage Transformer : Demagnetization

    The MVCT produces high voltages and currents during the performance of tests. DO NOT TOUCH connector clips or test leads while the MVCT is performing a test. Turn Power ON/OFF switch to ON. After boot up, in the Home Screen put the MVCT in voltage transformer testing mode by selecting the VT button.
  • Page 146 Select the “Demagnetization” button In the VT section of the Home Screen. This will activate a connection diagram showing how to correctly connect the MVCT to the VT Figure 119 VT Demagnetization Connection Diagram Check all connections to ensure correctness 9.

  • Page 147: Testing Voltage Transformer: Self Diagnostic

    Figure 120 VT Demagnetization Screen –Abort 12. Upon completion of process the VT will be left in a demagnetized state Demagnetization process is performed on an instrument transformer to remove any magnetizing forces on the windings that can effect the accuracy and performance of the instrument transformer Testing Voltage Transformer: Self Diagnostic Refer to the safety instructions first before use of the equipment.
  • Page 148 TOUCH connector clips or test leads while the MVCT is performing a test. Turn Power ON/OFF switch to ON. After the boot up, in the Home Screen, place the MVCT in voltage transformer testing mode by selecting the VT button at the top of the screen.

  • Page 149: Testing Relays With Mvct

    8.0 Testing Relays with MVCT For proper operation and control of the relay testing functionality, please refer to the User Guide for Megger’s SMRT1 Single Phase Relay Test System 9.0 Service Data Preventive Maintenance The unit utilizes surface mount technology (SMT) and other components which require little or no service except for routine cleaning, etc.

  • Page 150: Examine The Unit Every Six Months For

    Upgrade via Compact Disk Where internet access may not be available or blocked on your computer, Megger can provide a CD with the latest version of software on it. Contact your local Megger representative to order a copy of the firmware.

  • Page 151: Service And Repair Instructions

    The troubleshooting information relies on the technician to have a good understanding of the operation of the unit. The technician should contact the factory should they have any questions regarding the operation of the unit. Provide the Megger the serial number of the STVI when making inquiries.

  • Page 152: Preparation For Reshipment

    Erratic operation, no display, or a dim display. High voltage: Circuit breaker operation on MVCT unit, power supply failure. a. For MVCT, the internal power supply needs to be repaired or replaced, contact the factory for further instructions. 9.2.1.2 Ethernet Cable...
  • Page 153 Pack the equipment appropriately to prevent damage during shipment. If a reusable container is utilized, the unit will be returned in the same shipping container if it is in suitable condition. Add the Return Authorization Number to the address label of the shipping container for proper identification and quicker handling.

  • Page 154: Appendix I Cts Mounted On Transformer Bushings

    Appendix I CTs Mounted on Transformer Bushings...

  • Page 157: Appendix Ii Testing Ct In Reactor

    Appendix II Testing CT in Reactor Connection Diagram Single Phase Reactor Tests Set Connections CT Locations X1 X2 Jumpers Secondary of CT located in control U Bushing Neutral Bushing All CT not under Neutral Bushing cabinet Test U Bushing Neutral Bushing All CT not under U Bushing Secondary of CT...
  • Page 158 Connection Diagram Three Phase Reactor Tests Set Connections CT Locations X1 X2 Jumpers All CT not under Test X Bushing Secondary of CT X Bushing Neutral Bushing X Bushing - GND located in control Y Bushing - GND cabinet Z Bushing - GND All CT not under Test X Bushing - GND...

  • Page 159: Appendix Iii Cts Inside Delta Connection

    Appendix III CTs Inside Delta Connection...

Table of Contents