Mitsubishi Electric FR-A862 Instruction Manual page 79

Measurement of main circuit voltages, currents and powers
Measuring points and instruments
Item
Power supply Across R/L1 and S/L2,
voltage S/L2 and T/L3,
V T/L3 and R/L1
1
Power supply side
R/L1, S/L2, T/L3 line
current
current
I
1
R/L1, S/L2, T/L3 and
Power supply side
Across R/L1 and S/L2,
power
S/L2 and T/L3,
P
1
T/L3 and R/L1
Calculate after measuring power supply voltage, power supply side current and power supply side power.
Power supply side
power factor
Pf 1
Converter output Across P/+ and N/-
Operation enable
signal Across RDI, OH,
External thermal RES(+) and SD (for
relay signal sink logic)
Reset signal
Across A1 and C1
Alarm signal
Across B1 and C1
Output side
Across U and V, V and
voltage
W, and W and U
V 2
Output side
U, V and W line
current
currents
I 2
U, V, W and
Output side power
across U and V, V and
P
2
W
Calculate in similar manner to power supply side power factor.
Output side power
factor
Pf
2
Frequency setting Across 2, 4(+) and 5
signal Across 1(+) and 5
Frequency setting Across 10(+) and 5
power supply
Across 10E(+) and 5
Across AM(+) and 5
Frequency meter
signal
Across FM(+) and SD
Start signal
Select signal
Reset signal
Output stop signal
Across STF, STR, RH,
RM, RL, JOG, RT, AU,
STOP, CS, RES,
MRS(+) and SD (for
sink logic)
Across A1 and C1
Fault signal
Across B1 and C1

Use an FFT to measure the output voltage accurately. A tester or general measuring instrument cannot measure accurately.

When the carrier frequency exceeds 5 kHz, do not use this instrument since using it may increase eddy current losses produced in metal parts
inside the instrument, leading to burnout. In this case, use an approximate-effective value type.

When the setting of Pr.195 ABC1 terminal function selection is the positive logic
78
PRECAUTIONS FOR MAINTENANCE AND INSPECTION
Measuring point Measuring instrument
Digital power meter (for inverter)
P
1
----------------------- - 
Pf = 100
%
1

3V I
1 1
Such as tester
Digital multimeter or other tester,
or moving-coil type instrument
(internal resistance 50 k or more)
Digital multimeter or other tester
Digital power meter (for inverter)
Digital power meter (for inverter)
P
2

----------------------- -
Pf = 100
%
2

3V I
2 2
Digital multimeter or other tester,
or moving-coil type instrument
(internal resistance 50 k or more)
Digital multimeter or other tester
Remarks (reference measured value)
Commercial power supply
Within permissible AC voltage fluctuation (Refer
to page 82.)
P 1 = W 11 + W 12 + W 13 (3-wattmeter method)
Inverter LED is lit. 1.35  V
When open
20 to 30 VDC
ON voltage: 1 V or less
Continuity check

[Normal]
Across A1 and C1 Discontinuity
Across B1 and C1 Continuity
Difference between the phases is within 1% of
the maximum output voltage.

Difference between the phases is 10% or lower
of the rated inverter current.
P = W + W
2 21 22
2-wattmeter method (or 3-wattmeter method)
0 to 10 VDC, 4 to 20 mA
0 to 5 VDC and 0 to 10 VDC
5.2 VDC
10 VDC
Approximately 10 VDC at maximum
frequency
(without frequency meter)
Approximately 5 VDC at maximum
frequency
(without frequency meter)
T1
8 VDC
T2
Pulse width T1: Adjust with Pr.900.
Pulse cycle T2: Set with Pr.55.
(frequency monitor only)
When open
20 to 30 VDC
ON voltage: 1 V or less
Continuity check

[Normal]
Across A1 and C1 Discontinuity
Across B1 and C1 Continuity
1
"SD" is
common.
[Fault]
Continuity
Discontinuity
"5" is
common.
"SD" is
common.
[Fault]
Continuity
Discontinuity