Megger MVCT - Testing Voltage Transformer - Saturation;Excitation Test

To Next Page

To Previous Page

135

Figure 107 VT Ratio Test Results

7.3 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).

2. Connect the ground wing nut to a suitable ground.

3. Connect the test set secondary output binding posts X1 and X5 to secondary of the current

transformer on the desired tap. Observe the polarity marks on the VT (X1 on test set is polarity

terminal).

WARNING

There is always the possibility of voltages being induced at the terminals of a test

specimen because of proximity to high voltage energized lines. A residual static voltage

charge may also be present at these terminals. Ground each terminal to be tested with a

safety ground stick, before making connections.

Main Page

Table of Contents2
Mvct12
Introduction12
Terminology12
Acronyms12
MVCT Unpack and Preparation for Use13
Contents of MVCT Kit13
Assembly and Installation15
Communication Ports15
Ethernet Ports on MVCT15
Ethernet Ports on Display16
USB 2.0 Interface on Display16
Supply Voltage16
Figure 1 Ethernet Ports16
Figure 2 Ethernet Port to Power Display16
Figure 3 USB Port16
Operating System17
Basic Theory of Operation17
General17
CT Testing17
Ratio Test17
Polarity Test18
Excitation Test20
Insulation Resistance Test21
Burden Test22
Secondary Winding Resistance23
Powering System23
Initial Start up23
User Interface24
Integrated Display or Smart Touch View Interface24
Figure 4 Initial Screen24
Personal Computer Interface25
Figure 5 Instrument Connection Screen25
Figure 6 Boot up Home Screen25
Figure 7 Powerdb Lite Initial Screen26
Figure 8 Instrument Configuration Dialog27
Figure 9 Form Selection Dialog27
Figure 10 Instrument Logon Screen28
Figure 11 Connection Dialog28
Software Interface29
Figure 12 Powerdb Lite Home Screen29
Testing Mode32
CT Testing Mode - Menu Items32
Figure 13 Device Settings - CT Testing33
Figure 14 Name Plate Data - CT Testing Mode36
Figure 15 Home Screen CT Testing38
Figure 16 Run All Test Screen39
Figure 17 Manual Test Screen40
Figure 18 Manual Test Connection Diagram42
Figure 19 Manual Test Example44
Figure 20 Demagnetization Connection Diagram45
Figure 21 Demagnetization Process46
Figure 22 Self Test Connection Diagram47
Figure 23 Saturation Test Screen48
Figure 24 Ratio Test Screen49
Figure 25 Winding Resistance Test Screen51
Figure 26 Insulation Resistance Test Screen53
Figure 27 Burden Test Screen54
Figure 28 Sample CT Test Report55
Figure 29 Sample Multi Tap Test Report57
Figure 30 Ratio and Phase Error Tables58
Figure 31 Report Tap Configuration Dialog59
Figure 33 Excitation Curve Data60
Figure 34 View Excitation Data Points61
Figure 35 File Operation Tool Bar61
Figure 36 File Manager Screen62
Figure 37 File Operations Using PC63
VT Testing Mode - Menu Items64
Figure 38 File Save Using PC64
Figure 39 Device Settings - VT Testing64
Figure 40 Name Plate Data - VT Testing Mode67
Figure 41 Home Screen VT Testing Mode69
Figure 42 Run All Test Screen70
Figure 43 Demagnetization Connection Diagram71
Self Test72
Figure 44 Demagnetization Process72
Figure 45 VT Ratio Test Screen73
Figure 46 Saturation Test Screen74
Relay Testing Mode81
Testing CT with MVCT82
Test Plan Creation82
CT Saturation Test86
Method 1 - Concurrent86
Method 2 - Non Concurrent or Testing a Single Tap90
Ratio Test94
Method 1 - Concurrent94
Method 2 - Non Concurrent or Testing a Single Tap98
CT Winding Resistance Test103
Method 1 - Concurrent103
Method 2 - Non Concurrent or Testing a Single Tap107
Insulation Test111
Burden Test114
Manual Test118
Demagnetization121
Self Test123
Testing Vt's with MVCT125
Running a Complete Test of VT and Test Plan Creation125
Testing VT Ratio and Phase131
Testing Voltage Transformer - Saturation/Excitation Test135
Testing Voltage Transformer Winding Resistance138
Testing Voltage Transformer: Secondary Short Circuit Impedance141
Testing Voltage Transformer : Demagnetization145
Testing Voltage Transformer: Self Diagnostic147
Testing Relays with MVCT149
Service Data149
Preventive Maintenance149
Examine the Unit Every Six Months for150
Upgrading Software150
Service and Repair Instructions151
Basic Troubleshooting151
Preparation for Reshipment152
Appendix I Cts Mounted on Transformer Bushings154
Appendix II Testing CT in Reactor157
Appendix III Cts Inside Delta Connection159

Megger MVCT - Testing Voltage Transformer - Saturation;Excitation Test

Table of Contents

Related product manuals