Measurement of main circuit voltages, currents and powers
Measuring Points and Instruments
Item
Measuring Point
R/L1 and S/L2
Power supply voltage
S/L2 and T/L3
V1
T/L3 and R/L1
Power supply side
R/L1, S/L2, T/L3 line
current
current
I1
R/L1, S/L2, T/L3 and
Power supply side
R/L1 and S/L2,
power
S/L2 and T/L3,
P1
T/L3 and R/L1
Calculate after measuring power supply voltage, power
supply side current and power supply side power.
Power supply side
[Three-phase power supply]
power factor
Pf1
Pf
Across U and V,
Output side voltage
V and W,
V2
W and U
Output side current
U, V and W line currents
I2
U, V, W and
Output side power
U and V,
P2
V and W
Calculate in similar manner to power supply side power factor.
Output side power
factor
Pf
Pf2
Converter output
Across P/+ and N/-
Frequency setting
Across 2(+) and 5
signal
Across 4(+) and 5
Frequency setting
Across 10(+) and 5
power supply
Frequency meter
Across FM(+) and SD
signal
Across SD and the
Start signal
following:
Select signal
STF, STR, RH, RM, or
RL(+)
Reset
Across RES(+) and SD
Output stop
Across MRS(+) and SD
Across A and C
Fault signal
Across B and C
Use an FFT to measure the output voltage accurately. An FA tester or general measuring instrument cannot measure accurately.
When the setting of Pr.192 A,B,C terminal function selection is positive logic.
A digital power meter (designed for inverter) can also be used to measure.
296
Measuring Instrument
Moving-iron type AC voltmeter
Moving-iron type AC ammeter
Digital power meter (designed
for inverter) or electrodynamic
type singlephase wattmeter
P
1
----------------------- -
%
=
100
1
3V
I
1
1
Rectifier type AC voltage meter
,
(moving-iron type cannot
measure)
Approximate effective-value
rectifier type AC ammeter
Digital power meter (designed
for inverter) or electrodynamic
type singlephase wattmeter
P
2
----------------------- -
%
100
2
3V
I
2
2
(tester and such may be used)
(internal resistance 50k or more)
Commercial power supply
Within permissible AC voltage fluctuation
(Refer to page 302)
P
1
Difference between the phases is within 1% of the
maximum output voltage.
Difference between the phases is 10% or lower of
the rated drive unit current.
P
2
2-wattmeter method (or 3-wattmeter method)
Drive unit LED display is lit. 1.35 V1
Moving-coil type
(such as tester)
380V maximum during regeneration
DC0 to 10V, 4 to 20mA
DC5.2V
Approximately 5VDC at maximum
frequency (without frequency meter)
Moving-coil type
Pulse width T1: Adjust with C0 (Pr.900)
Pulse cycle T2: Set with Pr.55
(frequency monitor only)
When open
20 to 30VDC
ON voltage: 1V or less
Electric continuity check
Moving-coil type
(such as tester)
Across A and C
Across B and C
Remarks (Reference Measured Value)
=W
+W
+W
11
12
13 (3-wattmeter method)
=W
21
+W
22
T1
DC8V
T2
<Normal>
Discontinuity
Continuity
"5" is
common
"SD" is
common.
<Fault>
Continuity
Discontinuity