DOC. MIE91093 Rev. 1.34
Page 46 of 145
1.5.4. V-I curve test
The V-I curve is tested setting the phase shift at MTA, and
modifying the current at constant voltage, or the voltage at
constant current. In our figure we have two points: P1 = 100
V, 5 mA; P2 = 6 V, 1 A.
Test of P1
. Press ON. Set the auxiliary voltage 100 V.
. The phase angle is not displayed with very low currents; so,
adjust the current angle to 90°, taking the mains as a
reference:
AUX VAC/VDC > Aux Vac control > Phase > Reference:
Current > (90°) ESC
. Use the 10 A range ; connect the 2200 Ohm resistor in series
to Io relay input. For a better reading, connect also in series
the 25 mA input of the external measurement, selecting this
measurement as follows:
METERS > External > 20 mA ESC
. Slowly increase the current, until the relay trips: P1 trip is
found. As the relay trips, pressing the multi-function knob
tripping values can be saved. The TRIP LED (43) turns on for 5
seconds; during 5 seconds, parameters at trip are displayed;
then, the standard measurement is restored. Confirm save
results pressing the multi-function knob, and proceed: the
display shows the corresponding single-phase power.
. From this current value, slowly reduce it, until the relay
resets: P1 drop-off is found. As the relay resets, pressing the
multi-function knob drop-off values can be saved.
Test of P2
. Press ON. Set the auxiliary voltage at 0 V.
. Use the 10 A range ; there I no problem with phase and
current measurements. Adjust the current to 1 A.
. Slowly increase the voltage, until the relay trips: P2 trip is
found. As the relay trips, pressing the multi-function knob
tripping values can be saved. The TRIP LED (43) turns on for 5
seconds; during 5 seconds, parameters at trip are displayed;