Megger NIM 1000, Руководство пользователя

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Electrical connection
14
When making electrical connections, the following points should be observed:
• When connected with the supplied PKC-1 high performance connection clamps,
the NIM 1000 is approved for measurements on low voltage installations in the
measurement category 600V CAT IV in accordance with IEC 61010-1.
• The input voltage live on the measurement cables serves simultaneously as
supply voltage and must remain within the range of 100 V and 480 V.
• The NIM 1000 must be connected to the neutral conductor and at least one
phase. If the neutral conductor is not accessible, the blue connection cable must
be connected to a free phase conductor.
• The connection should be made based on the principle of four-conductor
measurement. So two measurement cables (current and voltage) must be
connected to each conductor intended to be measured using a Kelvin clip.
Using the NIM 1000, measurements can be carried out in both single-conductor mode
(just L1–N) as well as in multi-conductor mode (all possible conductor combinations).
Measurements are only carried out on phases which are live with a suitable input
voltage. Accordingly, phases which have not been connected will not be taken into
account in multiple-conductor mode.
So, for special applications or for time-saving reasons, the conductor combinations to be
measured can be purposefully limited in the multiple-conductor mode by using a specific
connection configuration. The following table shows some examples of this:
Required
measurements
Phases to be
connected
Measured conductor pairs
(instead of the 6 possible
combinations)
L2–N N (blue)
L2 (black) L2–N
L1–L2 N (blue)
L1 (brown)
L2 (black) L1–N
L2–N
L1–L2
L2–L3
L2–N N (blue)
L2 (black)
L3 (grey) L2–N
L3–N
L2–L3
Measurements can also be carried out on IT networks using the NIM 1000.
Given the lack of a neutral conductor, in measurements on networks of this kind it is
recommended that the blue test lead be connected to a free phase.
If, however, all phases are assigned test leads in multi-conductor mode, it is advisable
that the blue test lead be connected to the station earth or, in the case of an emergency,
even an earthing spike, in order to avoid faults in the voltage- and frequency detection
(otherwise the measurement will not start).
Notes
Specific connection-
configurations
Connection to IT
networks