MI 3101 EurotestAT: Measurements
Line impedance / Voltage drop
62
ksc .......Correction factor for Isc (see chapter
4.4.2
).
U
n
Input voltage range (L-N or L1-L2)
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)
Note:
High fluctuations of mains voltage influence the measurement results. The noise
sign
is displayed in the message field in this case. Repeat the measurement.
Isc is not calculated in case the terminal voltage monitor does not detect voltage
state that corresponds to the selected supply system, indication
.
5.5.2 Voltage drop
The voltage drop is calculated based on the difference of line impedance at connection
points (sockets) and the line impedance at the reference point (usually the impedance at
the switchboard).
Circuits for voltage drop measurement
Figure 5.25: Phase-neutral or phase-phase voltage drop measurement – connection of
plug commander and 3-wire test lead
Voltage drop measurement procedure
Step 1: Measuring the impedance Zref at electrical installation origin
Select the
Z-LINE
function.
Select the
Δ
U
sub-function.
Select test
parameters
(optional).
Connect
test cable to the instrument.
Connect
the test leads to the origin of electrical installation (see figure 5.25).
Press the
F1
key to perform the measurement of Zref.
Step 2: Measuring the voltage drop
Keep the
Δ
U
sub-function selected.
Select test
parameters
(Fuse type must be selected).
Connect
test cable or plug commander to the instrument.
Connect
the test leads to the tested points (see figure 5.25).
Press the
TEST
key to perform the measurement.
After the measurement is finished
Store
the result (optional).
