METREL EurotestXE, Инструкция по эксплуатации

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MI 3102(H) BT Eurotest XE Measurements
50
Fault loop impedance measurement procedure

Select the ZLOOP function using the function selector keys.

Set sub-function to Zloop or Zs rcd using the UP / DOWN keys.

Select test parameters (optional).

Connect test cable to the instrument.

Connect test leads to the item to be tested (see Figure 5.20 and Figure 5.27 ).

Press the TEST key to perform the measurement.

Store the result by pressing the MEM key (optional).
Figure 5.28: Example of loop impedance measurement result
Displayed results:
Z ............... fault loop impedance
Isc ............ prospective fault current,
Lim ........... low limit prospective short-circuit current value
Prospective fault current I
SC
is calculated from measured impedance as follows:
Z
k Un
I
SC
SC


where:
Un ......... Nominal U
L-PE
voltage (see table below),
ksc ........ Correction factor for Isc (see chapter 4.4.6Isc factor ).
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)
Notes:

High fluctuations of mains voltage can influence the measurement results (the noise sign
is displayed in the message field). In this case it is recommended to repeat few
measurements to check if the readings are stable.

This measurement will trip-out the RCD in RCD-protected electrical installation if test
Zloop is selected.

Select Zs rcd measurement to prevent trip-out of RCD in RCD protected installation.