ZES ZIMMER LMG450, Руководство пользователя

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Installation LMG450
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3.3.10 Measurements at middle and high voltage systems without N
LO
A
D
L 1
S 1 S 1 S 1 S 1 S 1
P 1 P 1 P 1 P 1
C T 1 C T 2 V T1 V T2
S 2 S 2 S 2 S 2 S 2
P 2 P 2 P 2 P 2
L 3
L 2
Figure 12: Measuring circuit for measuring in middle and high voltage sytems without N
Using star to delta conversion
This is the measuring circuit for measuring in middle and high voltage systems without the
neutral N. You can see that there is no PE conductor. You just need each two transformers for
voltages and currents. The chosen wiring should be ‘3+1, U
∆
I*->U
∆
I
∆
’ or ‘3+1, U
∆
I*-
>U*I*’.
When using voltage or current transformers please watch the applicable safety standards (e.g.
earthing, isolation, ...)!