MI 2892 Power Master
Recording Practice and Instrument Connection
126
Table 4.2: Connection check description and screen symbols
Measure
ment
Status
Description
Action to resolve issue
U
Measured voltage is within 90% ÷ 110%
range. All voltage measurements (RMS,
harmonics, voltage events) are valid.
U
Measured voltage is not within 90% ÷
110% range of Nominal voltage. All
voltage measurements (RMS, harmonics,
voltage events) can be compromised.
Set correct Nominal voltage value
and check voltage leads.
I
Measured current is within 10% ÷ 110% of
selected clamp measuring range. All
current measurements (RMS, harmonics,
voltage events) are valid.
I
Measured current is within 5% ÷ 10% of
selected clamp measuring range.
If higher current is expected
during recorder campaign, this
waning can be ignored. Otherwise
it is recommended to decrease
current range.
I
Measured current is less than 5% of clamp
measuring range. Accuracy of current
measurements (RMS, harmonics…) can be
compromised.
Go to Current clamp settings and
change Clamp Measuring Range
or press AUTOSET I button and
let instrument to choose optimal
current range.
Phase
Phase angle between voltage and current
is less than 90
0
. This indicate that
measured current flow in the same
direction
as
voltage.
Power
measurements are valid.
Phase
Phase angle between voltage and current
is more than 90
0
. This indicate that
measured current has opposite flow than
voltage.
Power
measurements
are
compromised.
Check clamp direction (
icon is
present in status bar) and see if
current channel correspond to the
voltage channel (if current I
1
is
measured on voltage U
1
)
Useq
123
Voltage sequence is correct. Unbalance
and power measurement are valid.
Useq
321
Voltage sequence is reverse. Unbalance
and
power
measurement
are
compromised.
Switch voltage leads U
2
and U
3
in-
between to obtain right sequence.
Useq
-
Phase angle between voltages is not 120
0
±
30
0
.
Unbalance
and
power
measurement are compromised.
Check voltage leads, and check if
selected Connection correspond
to the actual network.
Iseq
123
Current sequence is correct, phase angle
between currents is less than 120
0
± 60
0
.
Unbalance and power measurement are
valid.
