METREL MultiServicerXD MI 3325, Инструкция по эксплуатации

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MI 3325 MultiServicerXD Single tests
107
6.2.16 Z loop
– Fault loop impedance and prospective fault current
Warning!

MI 3325 checks voltage on TP1-PE terminal before running test and disables test
in case the hazardous live voltage is detected. In this case, immediately remove
supply from tested circuit, find, and eliminate problem before any other activity!
See chapter
1.2 Testing potential on TP1-PE terminal for installation tests for more
information.
Figure 6.64: Z loop menu
Test results / sub-results
Z
Loop impedance
Ipsc Prospective fault current
Ulpe Voltage L-PE
R Resistance of loop impedance
XL
Reactance of loop impedance
Prospective fault current I
PSC
is calculated from measured impedance as follows:
Z
k U
I
SC N
PSC


U
n
......... Nominal U
L-PE
voltage (see table below),
k
sc
........ Correction factor (Isc factor) for I
PSC
. See chapter 4.7.3 Settings for more information.
U
n
Input voltage range (L-PE)
110 V (93 V

U
L-PE

134 V)
230 V (185 V

U
L-PE

266 V)
Table 6.2: Relations between Input voltage
– U
L-PE
and nominal voltage
– U
n
used for
calculation
Test parameters
Fuse Type Selection of fuse type [gG, NV, B, C, D, K, Off, Custom]
Fuse I Rated current of selected fuse
Fuse t Maximum breaking time of selected fuse
Isc factor Correction factor Isc [0.2
… 3.0]
Test
1)
Selection of test [-, L/PE, L1/PE, L2/PE, L3/PE]
Earthing system [ TN/TT, IT ] Refer to chapter 4.7.3 Settings for more information.
1)
With Plug test cable Z loop is measured in the same way regardless of the setting. The
parameter is meant for documentation.
Refer to Fuse tables guide for detailed information on fuse data.