METREL MI 3399, Инструкция с упражнениями

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Electrical Installation Safety Trainer AD 1 - MI 3399
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2.3 Fault loop impedance measurement
Fault loop is a loop comprising mains source, line wiring and PE return path to the
mains source. Scope of loop impedance test is:

To verify effectiveness of installed over current and / or residual current
disconnection devices.

To verify fault loop impedances, prospective fault currents and fault voltage
values.
Figure 2-10: Chart reference for fault loop impedance measurements
– TN system
Figure 2-11: Chart reference for fault loop impedance measurements
– TT system
Figure 2-12: Measuring Z
Loop
in Application Trainer’s switchboard with cables on the
supply side (before the RCD)