METREL MultiServicerXD MI 3325, Instruction Manual

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MI 3325 MultiServicerXD Appendix B
188
6.2.21 Z auto - Auto test sequence for fast line and loop testing
6.2.22 Voltage Drop
Test parameters
Fuse Type Selection of fuse type [gG, NV, B, C, D, K, Off, Custom]
Isc factor Correction factor Isc
[0.2 … 3.0]
Test limits
Ia(Ipsc)
Minimum fault current for selected fuse
are replaced with
Test parameters
Fuse Type Selection of fuse type [B, C, D, Fuse, Off, Custom]
Z factor Z factor [1, 1.04]
Test limits
Zlim(Z)
Zlim(Z (LPE), Z (LN))
Maximum loop / line impedance for selected fuse or custom value.
Figure B.4: Examples of Z line, Z loop and Z auto measurement result
Prospective fault / short circuit current I
PSC
is calculated from measured impedance as follows:
Z
U
I
N
PSC

Loop / line impedance limit Z
Lim(Z)
for selected fuse is calculated from the following formula:
Lim Z Lim
Z factor Scaling Z
 
_
) (
where:
Zlim .......................... Maximum loop / line impedance for selected fuse
Scaling factor ............ Impedance correction factor (Z factor)
Un ............................. Nominal U
L-PE
voltage
Modifications in chapter
6.2.28 RCD t
– Trip-out time:
Added new test parameter and sub-result:
Test parameter
Random phase [No, Yes]
Test results / sub-results
Phase Starting phase (if Random phase parameter is enabled)