Fuji Electric RHC-D 690V Series, Руководство пользователя

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8.3 Measurement of Electrical Quantity in Main Circuit
Because the voltage and current of the main circuit power supply (input) and DC output of the converter contain
harmonic components, the readings may vary with the type of the meter. Use meters specified in Table 8.3-1 when
measuring with meters for commercial frequencies. For measurement at the inverter side, refer to the inverter
instruction manual.
The power factor cannot be measured by a commercially available power-factor meter that measures the phase
difference between the voltage and current. To obtain the power factor, measure the power, voltage and current on
each of the input and output sides and use the following formula.
Power factor =
x 100(%]
Table 8.3-1 Meters for Measurement of Main Circuit
Item
Input (power supply) side
DC link bus voltage
(Between P(+) and N(-))
Voltage Current
Name of meter
Ammeter
A
R, S, T
Voltmeter
V
R, S, T
Wattmeter
W
R, T
DC voltmeter
V
Type of meter
Moving iron type
Rectifier or
moving iron type
Digital AC power meter Moving coil type
Symbol of meter -
Note: Because the waveform at the input terminals (L1/R, L2/S and L3/T) of the converter is under PWM, measurement
with a multimeter or the like causes large measurement errors. To measure the input voltage, measure at the point shown in
Figure 8.3-1.
M
E(G)
U
V
W
N(-)
P(+)
L1/R
L2/S
L3/T
E(G)
N(-)
P(+)
V
R
V
T
V
S
A
T
A
R
A
S
W
R
W
T
V
+
-
Converter Inverter
L1
L2
L3
E(G)
Filter stack
U0
V0
W0
Figure 8.3-1 Connection of Meters
Electric power(W)
√
3 x Voltage(V) x Current(A)
8-4