Mitsubishi Electric FR-CC2-P, Инструкция по эксплуатации

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Measurement of main circuit voltages, currents and powers
PRECAUTIONS FOR MAINTENANCE AND INSPECTION
161
7
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 converter unit output side
When the wiring length between the converter unit and the inverter is large, 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.
 Examples of measuring points and instruments
 Measuring points and instruments

When the setting of Pr.195 ABC1 terminal function selection is the positive logic
Item Measuring point Measuring instrument Remarks (reference measured value)
Power supply
voltage
V1 Across R/L1 and S/L2,
S/L2 and T/L3,
T/L3 and R/L1
Digital power meter (designed for
inverter)
Commercial power supply
Within permissible AC voltage fluctuation (Refer to
page 166 .)
Power supply side
current
I1
R/L1, S/L2, T/L3 line
current
Power supply side
power
P1
R/L1, S/L2, T/L3 and
Across R/L1 and S/L2,
S/L2 and T/L3,
T/L3 and R/L1
P1=W11 + W12 + W13 (3-wattmeter method)
Power supply side
power factor
Pf1
Calculate after measuring power supply voltage, power supply side current and power supply side power.
Converter output Across P/+ and N/- Digital multimeter or other tester Converter unit LED is ON. 1.35

V1
Input signal
Across RDI, OH,
RES(+) and SD (for
sink logic) Digital multimeter or other tester
or moving-coil type instrument
(internal resistance 50 k
Ω or more)
When open
20 to 30 VDC
ON voltage: 1 V or less
"SD" is
common
Fault signal
Across A1 and C1
Across B1 and C1
Digital multimeter or other tester
Continuity check

[Normal] [Fault]
Across A1 and C1 Discontinuity Continuity
Across B1 and C1 Continuity Discontinuity
Ar
As
At
Vr
Vs
Vt
W11
W12
W13
Inverter/
Converter unit
Three-phase
power supply
To the motor
Input voltage
Input current
R/L1
S/L2
T/L3
P/+ N/-
Au
Av
Aw
Vu
Vv
Vw
W21
W22
V
U
V
W
Pf
1
P
1
3V
1
I

1
------------------------ 100 
= %