Measurement Of Main Circuit Voltages, Currents, And Powers - Mitsubishi Electric FR-CC2-N Series Instruction Manual

7.2
Measurement of main circuit voltages, currents,
and powers
Since the voltages and currents on the converter unit power supply and output sides include harmonics, measurement data
depends on the instruments used and circuits measured. When instruments for commercial frequency are used for
measurement, measure the following circuits with the instruments given on the next page.
NOTE
• When installing meters etc. on the output side of the converter unit:
When the wiring length between the converter unit and the inverter is long, the meters and CTs may generate heat due to line-
to-line leakage current. Therefore, choose the equipment which has enough allowance for the current rating.
Three-phase
power supply
 Measuring points and instruments
Item Measuring point
Between R/L1 and S/L2,
Power supply voltage
S/L2 and T/L3, and T/L3
V1
and R/L1
Input current Line current at R/L1, S/L2,
I1 and T/L3
At R/L1, S/L2, and T/L3,
Input power and between R/L1 and S/
P1 L2, S/L2 and T/L3, and T/
L3 and R/L1
Calculate after measuring input voltage, input current and input power.
Input power factor
Pf1
Pf
Converter output Between P/+ and N/-
Across terminals RDI, OH,
Input signal RES(+) and SD (for sink
logic)
Between A1 and C1
Fault signal
Between B1 and C1
*1 When the setting of Pr.195 ABC1 terminal function selection is the positive logic.
Ar
W11
Vr
As
W12
Vs
At W13
Vt
Measuring instrument
Digital power meter (designed for
inverter)
P
1
= x 100%
1
I
x
3V
1
1
Tester such as a digital
multimeter.
Tester such as a digital
multimeter, or moving-coil type
instrument (internal resistance
50 kΩ or more)
Digital multimeter or other tester
Input voltage
Input current
Converter unit
R/L1 P/+
S/L2
V
T/L3 N/-
Remarks (reference measured value)
Commercial power
Within permissible AC voltage fluctuation. (Refer to
page 166.)
P1 = W11 + W12 + W13 (3-wattmeter method)
Inverter LED indication 1.35 × V1
Voltage when terminal is open: 20 to
30 VDC.
Voltage when signal is ON: 1 V or
less.
Continuity test
Normal: discontinuity across A1 and C1 (continuity
across B1 and C1)
Fault: continuity across A1 and C1 (discontinuity
across B1 and C1)
7. PRECAUTIONS FOR MAINTENANCE AND INSPECTION

7.2 Measurement of main circuit voltages, currents, and powers

+
To the inverter
-
Terminal SD
is a common
terminal.
*1
1
2
3
4
5
6
7
8
9
10
161