Mitsubishi Electric FR-A741-11K, Инструкция пользователя

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170
Measurement of main circuit voltages,
currents and powers
Measuring points and instruments
*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
Item
Measuring
Point
Measuring Instrument Remarks (Reference Measured Value)
Power supply voltage
V
1
Across R/L1-S/
L2, S/L2-T/L3, T/
L3-R/L1
Moving-iron type AC voltmeter
Commercial power supply
Within permissible AC voltage fluctuation
(Refer to
page 174 )
Power supply side
current
I
1
R/L1, S/L2, and
T/L3 line currents
Moving-iron type AC ammeter
Power supply side
power
P
1
R/L1, S/L2, T/L3 and
R/L1-S/L2, S/L2-T/
L3, T/L3-R/L1
Electrodynamic type single-phase
wattmeter
P1=W11+W12+W13 (3-wattmeter method)
Power supply side
power factor
Pf
1
Calculate after measuring power supply voltage, power supply side current and power supply side power.
Output side voltage
V
2
Across U-V, V-W
and W-U
Rectifier type AC voltage meter
*1
(Moving-iron type cannot
measure)
Difference between the phases is within ±1% of
the maximum output voltage.
Output side current
I
2
U, V and W line
currents
Moving-iron type AC ammeter
*2
Difference between the phases is 10% or lower of
the rated inverter current.
Output side power
P
2
U, V, W and U-V,
V-W Electrodynamic type single-phase
wattmeter P
2
= W
21
+ W
22
2-wattmeter method (or 3-wattmeter method)
Output side power
factor
Pf
2
Calculate in similar manner to power supply side power factor.
Converter output Across P/
+
-N/
−
Moving-coil type (such as tester) Inverter LED display is lit. 1.35
×
V1
Frequency setting
signal
Across 2, 4(+)-5
Moving-coil type
(Tester and such may be used)
(Internal resistance: 50k
Ω
or
larger)
0 to 10VDC, 4 to 20mA
"5" is
common
Across 1(+)-5 0 to ±5VDC, 0 to ±10VDC
Frequency setting
power supply
Across 10 (+) -5 5.2VDC
Across 10E(+)-5 10VDC
Frequency meter
signal
Across AM(+)-5
Approximately 10VDC at maximum
frequency
(without frequency meter)
Across FM(+)-SD
Approximately 5VDC at maximum
frequency
(without frequency meter)
Pulse width T1:
Adjusted by C0 (Pr. 900)
Pulse cycle T2: Set by Pr. 55
(Valid for frequency
monitoring only)
"SD" is
common
Start signal
Select signal
Across STF, STR,
RH, RM, RL, JOG,
RT, AU, STOP, CS
(+) -SD
When open
20 to 30VDC
ON voltage: 1V or less
Reset Across RES (+) -SD
Output stop Across MRS (+) -SD
Alarm signal
Across A1-C1
Across B1-C1 Moving-coil type
(such as tester)
Continuity check
*3
<Normal> <Abnormal>
Across A1-C1 Discontinuity Continuity
Across B1-C1 Continuity Discontinuity
Pf
1
= —————
×
100%
P
1
3
V
1
×
I
1
Pf
2
= —————
×
100%
P
2
3
V
2
×
I
2
8VDC
T1
T2