Sonel MPI-540 User Manual

MPI-540 – USER MANUAL
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3.4 Measurement of fault loop parameters
NOTE!
 If there are residual current devices in the network tested, they should be bypassed
by bridging for the period of impedance measurement. However, it should be re-
membered that the tested circuit is modified in this way and the obtained results
may slightly differ from the actual results.
 After completing measurements, always remove modifications introduced to the
tested system for the period of measurements and check the operation of the resid-
ual current switch.
 The above remarks do not apply to measurements of fault loop impedance with the
use of function Z
L-PE [RCD]
.
 Measurements of short-circuit loop impedance downstream the inverters are inef-
fective and measurement results unreliable. This is due to the fluctuations of inter-
nal impedance of the inverter during its operations. Do not perform measurements
of short-circuit loop impedance directly downstream inverters.
3.4.1 Settings of measurements
Select item Z
L-N
, Z
L-PE
or Z
L-PE[RCD]
.
The correctness of the measure-
ment depends on the correct ad-
justment of the length of leads.
If a WS type adapter has not
been connected to the meter,
standard manufacturer's lead
lengths are available in the menu.
In this case, touch the drop-down
list field.

Sonel MPI-540 Specifications

General

Brand	Sonel
Model	MPI-540
Category	Measuring Instruments
Language	English