METREL MI 3399, Инструкция с упражнениями

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Electrical Installation Safety Trainer AD 1 - MI 3399
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Other individual resistances can be measured by embracing other electrodes with the
current clamps.
Notes:

Applicable in complex earthing system with numerous parallel earthing electrodes.

Applicable for measuring earthing resistance in transformer stations.

Applicable for measuring lightning systems (Figure 2-57).

Applicable for measuring earthing resistance in TN earthing systems (Figure 2-58).

Especially suitable in urban area.

No disconnection of measured electrodes.

Very fast measurement; no need to place measurement probes and to separate the
measured electrodes.

Very accurate for resistances below 10 Ω.

The minimum distance between driver and sense clamps is at least 30 cm (unless
they are shielded).
Figure 2-57: Test system (individual earthing rods) with two current clamps
Figure 2-58: Measurement of resistance to earth of object with two current clamps in TN
system