Benning IT 115 - 5.6.1 Line Impedance and Short-Circuit Current

BENNING IT 115 Device description
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5.6.1 Line impedance and prospective short-circuit current
Connection plan
Figure 5.28: Connection of the optional "Commander" test plug (044149)
and the three-wire test cable
How to perform line impedance measurements
 Select the Z
I
(L-N/L) [English: Z
LINE
(L-N/L)] function by means of the function selector
switch.
 Set the sub-function to Zline.
 Set the testing parameters.
 Connect the test cables to the test object (see figure 5.28).
 Press the "TEST" key to start the measurement.
x
Figure 5.29: Example of a line impedance measurement
Results displayed:
Z ............... line impedance
Isc ............ prospective short-circuit current
Lim ........... lower limit of the prospective short-circuit current
The prospective short-circuit current is calculated as follows:
Z
kUn
I
SC
SC


with:
Un .......nominal voltage L-N or L1-L2 (see table below),
ksc ......correction factor for short-circuit current Isc (see chapter 4.4.6 Isc factor (scaling factor))
U
n
Voltage range (L-N or L1-L2)
110 V
(93 V  U
L
-
N
 134 V)
230 V
(185 V  U
L
-
N
 266 V)
400 V
(321 V  U
L
-
L
 485 V)