Megger MRCT, User Manual

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5.1 Ratio ........................................................................................................................................................... 48
5.2 Winding Resistance .............................................................................................................................. 49
6.0 Functions Available for All Configuration .............................................................. 51
6.1 File Operations ....................................................................................................................................... 51
7.0 Service Data ............................................................................................................. 53
7.1 Preventive Maintenance ................................................................................................................... 53
7.1.1 Examine the unit every six months for: ..................................................................... 54
7.1.2 Upgrading STVI Software ........................................................................................... 54
7.2 Service and Repair Instructions .................................................................................................... 55
7.2.1 Basic Troubleshooting ................................................................................................ 55
7.2.1.1 Power Input ................................................................................................................................ 56
7.2.1.2 Ethernet Cable ........................................................................................................................... 56
7.2.1.3 Ratio Errors ................................................................................................................................ 56
8.0 Preparation for Reshipment ................................................................................... 57
9.0 Step by Step Testing a CT with MRCT ................................................................. 57
9.1 Test Plan Creation and Testing of CT .......................................................................................... 57
9.2 CT Saturation Test ............................................................................................................................... 62
9.2.1 Method 1 – Concurrent ............................................................................................. 62
9.2.2 Method 2 – Non Concurrent or Testing a Single Tap ................................................. 66
9.3 CT Ratio Test .......................................................................................................................................... 69
9.3.1 Method 1 – Concurrent ............................................................................................. 69
9.3.2 Method 2 – Non Concurrent or Testing a Single Tap ................................................. 74
9.4 CT Winding Resistance Test: ........................................................................................................... 78
9.4.1 Method 1 – Concurrent ............................................................................................. 78
9.4.2 Method 2 – Non Concurrent or Testing a Single Tap ................................................. 82
9.5 CT Insulation Test: ............................................................................................................................. 86
9.6 CT Burden Test .................................................................................................................................... 89
9.7 Manual Test of CT ............................................................................................................................... 93
9.8 CT Demagnetization .......................................................................................................................... 96
10.0 Step by Step Testing a VT with MRCT .................................................................. 98
10.1 Voltage Transformer Ratio and Phase ....................................................................................... 98
10.2 Testing Voltage Transformer Secondary Winding Resistance .................................... 102
11.0 Self Test ............................................................................................................... 105