METREL MI 3399, Instruction Manual With Exercises

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Electrical Installation Safety Trainer AD 1 - MI 3399
30
2.3.1.3 Fault loop, fault impedance and prospective fault current in RCD protected TN and TT
systems 65
2.3.2 Exercises ........................................................................................................................................ 66
2.3.2.1 Exercise No. 2.3-1: Z
L-PE
and I
PFC
measurement on the supply side ...................................... 66
Measuring connection topology ........................................................................................................ 66
Measuring procedure ......................................................................................................................... 67
Expected results ................................................................................................................................. 68
Expected results with a simulated error ............................................................................................ 69
2.3.2.2 Exercise No. 2.3-2: Z
L-PE
and I
PFC
measurement on the socket side – RCD protected .......... 69
Measuring connection topology ........................................................................................................ 69
Measuring procedure ......................................................................................................................... 70
Expected results ................................................................................................................................. 71
Expected results with a simulated error ............................................................................................ 72
2.4 Measuring RCD parameters ...............................................................................75
2.4.1 Background of measurement ........................................................................................................ 75
2.4.1.1 Function of RCD ................................................................................................................... 76
2.4.2 Exercises ........................................................................................................................................ 78
2.4.2.1 Exercise No. 2.4-1: RCD trip-out time, current and contact voltage measurements .......... 78
Measuring connection topology ........................................................................................................ 78
Measuring procedure ......................................................................................................................... 78
Expected results ................................................................................................................................. 79
Expected results with a simulated error ............................................................................................ 80
2.4.2.2 Exercise No. 2.4-2: RCD trip-out time, current and contact voltage measurements in an IT
earthing system ...................................................................................................................................... 81
Measuring procedure ......................................................................................................................... 81
Expected results ................................................................................................................................. 82
2.5 Insulation monitor devices and measuring single fault leakage currents ......84
2.5.1 Background of measurement ........................................................................................................ 84
2.5.1.1 Single fault leakage current (I
SFL
) ......................................................................................... 84
2.5.1.2 Insulation monitor device (IMD) .......................................................................................... 85
2.5.2 Exercises ........................................................................................................................................ 85
2.5.2.1 Exercise No. 2.5-1: Measuring single fault leakage currents (I
SFL
) ....................................... 85
Measuring procedure ......................................................................................................................... 85
Expected results ................................................................................................................................. 86
Expected results with a simulated error ............................................................................................ 86
2.5.2.2 Exercise No. 2.5-2: Verification of insulation monitor devices (IMD) .................................. 87
Measuring procedure ......................................................................................................................... 87
Expected results ................................................................................................................................. 88
Expected results with a simulated error ............................................................................................ 89
2.6 Insulation resistance measurement ..................................................................90
2.6.1 Background of measurement ........................................................................................................ 91
2.6.1.1 Insulation resistance of individual circuits / items .............................................................. 92
2.6.2 Exercises ........................................................................................................................................ 92
2.6.2.1 Exercise No. 2.6-1: R
ISO
in a 1-phase outlet in a TN/TT system ............................................ 92
Measuring procedure ......................................................................................................................... 92
Expected results ................................................................................................................................. 93
Expected results with a simulated error ............................................................................................ 94
2.6.2.2 Exercise No. 2.6-2: R
ISO
in a 3-phase TN/TT system on the supply side ............................... 94
Measuring procedure ......................................................................................................................... 94
Expected results ................................................................................................................................. 95
Expected results with a simulated error ............................................................................................ 96