MI 3101 EurotestAT: Appendix D
IT supply systems
109
D.3.1 MI 3101 test functions and IT systems
The table below contains functions of the instrument including compatibility notes related
to the IT system.
IT system
functions Note
Voltage
Voltage
Symbols modified for IT system, see
figure
D.2.
Phase rotation
For three phase system only, automatic detection.
RCD functions
Not applicable.
RCD - Uc
RCD - Trip out Time t
RCD - Tripping Current
RCD – Automatic test
Loop functions
Not applicable.
Fault Loop Impedance
Fault Loop Prospective
Short-circuit Current
Line functions
Line Impedance
Impedance Z
Line-Line
.
Line Prospective
Short-circuit Current
I
SC
for rated U
Line-Line
.
Continuity functions
Independent of selected supply system.
Insulation Resistance
Independent of selected supply system.
Earth resistance
Independent of selected supply system.
PE test probe
Active, but does not inhibit selected test if voltage is detected.
D.3.1.1 Voltage measurements
Figure D.2: Voltage measurements
Displayed results for
single phase
system:
U21..........Voltage between line conductors,
U1pe........Voltage between line 1 and protective conductor,
U2pe........Voltage between line 2 and protective conductor.
D.3.1.2 Line impedance
See chapter
5.5
, the measurement is the same; only terminal voltage monitor indication
corresponds to IT system.
