Sonel MPI-506 User Manual

MPI-506 – USER MANUAL
11
3.4.2 Prospective short-circuit current
The meter always measures the impedance, and the displayed short-circuit current is calculat-
ed according to the following formula:
S
n
k
Z
U
I 
where:
U
n
– rated voltage of the tested mains,
Z
S
– measured impedance.
Based on the rated voltage U
n
selected in the general settings (section 2.2), the meter auto-
matically detects the measurement with phase-to-neutral or phase-to-phase voltage and includes this
in the calculations.
If the tested mains voltage is out of tolerance range, the meter will not be able to determine the
correct rated voltage for calculation of short-circuit current. In such case, horizontal lines will be dis-
played instead of the short-circuit current. The figure below shows the voltage ranges for which the
short-circuit current is calculated.
230
400
440
U [V]
U voltage ranges for which the
short-circuit current is calculated
L-N
Voltage range for which the impedance is measured
207
253
360
220
380
418
198
242
342
373
415
440
216
240
264
440
U [V]
U [V]
U =220V
n
U =230V
n
U =240V
n
U voltage ranges for which the
short-circuit current is calculated
L-L

Sonel MPI-506 Specifications

General

Brand	Sonel
Model	MPI-506
Category	Measuring Instruments
Language	English