4.7 Voltage measurement modes
4 Measurement functions
Technical description
142
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VM50.EN004
"1LL"
The device is connected to one line-to-line voltage. Single
phase voltage measurement and over- and undervoltage
protection are available. Directional earth fault protection is
not possible (see Figure 4.7-2 and Figure 8.10.2-2).
"1LN"
The device is connected to one phase-to-ground voltage.
Single phase voltage measurement is available. In low
impedance grounded networks over- and undervoltage
protection are available. Directional earth fault protection is
not possible (see Figure 4.7-3 and Figure 8.10.2-3).
Uo
L1
"Uo"
VAMP 52
L2 L3
10
11
Figure 4.7-1 VAMP 52 Broken delta connection in voltage measurement
mode “U
0
”.
1Line
"1LL"
VAMP 52
L1 L2 L3
10
11
Figure 4.7-2 VAMP 52 line-to-line voltage in voltage measurement mode
“1LL”.
1Phase
"1LN"
VAMP 52
L1 L2 L3
10
11
Figure 4.7-3 VAMP 52 phase-to-neutral voltage in voltage measurement
mode “1LN”.