Mitsubishi Electric FR-A720-0.4K Instruction Manual page 425

Measuring points and instruments
Measuring
Item
Point
Across R/L1-S/
Power supply voltage
L2, S/L2-T/L3, T/
V
1
L3-R/L1
Power supply side
R/L1, S/L2, and
current
T/L3 line currents
I
1
Power supply side R/L1, S/L2, T/L3 and
power R/L1-S/L2, S/L2-T/
P L3, T/L3-R/L1
1
Calculate after measuring power supply voltage, power supply side current and power supply side power.
Power supply side
power factor
= ————— × 100%
Pf
Pf
1 1
Output side voltage Across U-V, V-W
V and W-U
2
Output side current U, V and W line
I currents
2
Output side power U, V, W and U-V,
P V-W
2
Calculate in similar manner to power supply side power factor.
Output side power
factor
= ————— × 100%
Pf
2
Pf
2
Converter output Across P/+-N/−
Across 2, 4(+)-5
Frequency setting
signal
Across 1(+)-5
Across 10 (+) -5
Frequency setting
power supply
Across 10E(+)-5
Across AM(+)-5
Frequency meter
signal
Across FM(+)-SD
Across STF, STR,
Start signal RH, RM, RL, JOG,
Select signal RT, AU, STOP, CS
(+) -SD
Reset Across RES (+) -SD
Output stop Across MRS (+) -SD
Across A1-C1
Alarm signal
Across B1-C1
*1 Use an FFT to measure the output voltage accurately. A tester or general measuring instrument cannot measure accurately.
*2 When the carrier frequency exceeds 5kHz, do not use this instrument since using it may increase eddy-current losses produced in metal parts
inside the instrument, leading to burnout. If the wiring length between the inverter and motor is long, the instrument and CT may generate
heat due to line-to-line leakage current.
*3 When the setting of Pr. 195 ABC1 terminal function selection is positive logic
Measuring Instrument
Moving-iron type AC voltmeter
Moving-iron type AC ammeter
Electrodynamic type single-phase
wattmeter
P
1
× I
V
3
1 1
Rectifier type AC voltage meter
(Moving-iron type cannot
measure)
Moving-iron type AC ammeter
Electrodynamic type single-phase
wattmeter
P
2
× I
V
3
2 2
Moving-coil type (such as tester) Inverter LED display is lit. 1.35
Moving-coil type
(Tester and such may be used)
(Internal resistance: 50kΩ or
larger)
Moving-coil type
(such as tester)
Measurement of main circuit voltages,
currents and powers
Remarks (Reference Measured Value)
Commercial power supply
Within permissible AC voltage fluctuation
(Refer to page 420)
P1=W11+W12+W13 (3-wattmeter method)
*1
Difference between the phases is within ±1% of
the maximum output voltage.
Difference between the phases is 10% or lower of
*2
the rated inverter current.
P = W + W
2 21 22
2-wattmeter method (or 3-wattmeter method)
0 to 10VDC, 4 to 20mA
0 to ±5VDC, 0 to ±10VDC
5.2VDC
10VDC
Approximately 10VDC at maximum
frequency
(without frequency meter)
Approximately 5VDC at maximum
frequency
(without frequency meter)
T1
8VDC
T2
Pulse width T1:
Adjusted by C0 (Pr. 900)
Pulse cycle T2: Set by Pr. 55
(Valid for frequency
monitoring only)
When open
20 to 30VDC
ON voltage: 1V or less
Continuity check
*3
<Normal>
Across A1-C1 Discontinuity
Across B1-C1 Continuity
×
V1
"5" is
common
"SD" is
common
<Abnormal>
Continuity
Discontinuity
6
415