MI 2883 Energy Master
Operating the instrument
55
Figure 3.36: Phase diagram screen
Table 3.34: Instrument screen symbols and abbreviations
U1, U2, U3
Fundamental voltages Ufund
1
, Ufund
2
, Ufund
3
with relative phase
angle to Ufund
1
U12, U23, U31 Fundamental voltages Ufund
12
, Ufund
23
, Ufund
31
with relative phase
angle to Ufund
12
I1, I2, I3
Fundamental currents Ifund
1
, Ifund
2
, Ifund
3
with relative phase angle
to Ufund
1
or Ufund
12
Table 3.35: Keys in Phase diagram screen
HOLD
Holds measurement on display. Hold clock time will be
displayed in the right top corner.
RUN
Runs held measurement.
U
I
I
U
Selects voltage for scaling (with cursors).
Selects current for scaling (with cursors).
METER
Switches to PHASE DIAGRAM view.
UNBAL.
Switches to UNBALANCE DIAGRAM view.
TREND
Switches to TREND view (available only during recording).
Scales voltage or current phasors.
Triggers Waveform snapshot.
Returns
to the “MEASUREMENTS” submenu.
3.10.2
Unbalance diagram
Unbalance diagram represents current and voltage unbalance of the measuring system.
Unbalance arises when RMS values or phase angles between consecutive phases are
not equal. Diagram is shown on figure below.
F1
F2
F4