METREL EurotestXC MI 3152, Инструкция по эксплуатации

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MI 3152(H) Eurotest XC (2,5 kV) Tests and measurements
120
Measurement procedure

Enter the Z line function.

Set test parameters / limits.

Connect test cable to the instrument.

Connect test leads or Plug commander to the object under
test, see Figure 7.43 .

Start the measurement.

Save results (optional).
Figure 7.44: Examples of Line impedance measurement result
Measurement results / sub-results
Z Line impedance
Ipsc Prospective short-circuit current
Uln
Voltage measured between L/L1
– N/L2 test terminals
R Resistance of line impedance
XL Reactance of line impedance
Imax3p
Maximal three-phases prospective short-circuit current
Imin3p Minimal three-phases prospective short-circuit current
Imax2p Maximal two-phases prospective short-circuit current
Imin2p Minimal two-phases prospective short-circuit current
Imax
Maximal single-phase prospective short-circuit current
Imin Minimal single-phase prospective short-circuit current
Prospective short circuit current I
PSC
is calculated as follows:
Z
k U
I
SC N
PSC


where:
U
n
......... Nominal U
L-N
or U
L-L
voltage (see table below),
k
sc
........ Correction factor (Isc factor) for I
PSC
. Refer to chapter 4.6.5 Settings for more
information.
U
n
Input voltage range (L-N or L-L)
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)
Table 7.5: Relationship between Input voltage
– U
L-N(L)
and nominal voltage
– U
n
used for
calculation