PROTECTIVE FUNCTIONS
40
Measuring Points and Instruments
Item Measuring Point Measuring Instrument Remarks
(Reference Measured Value)
Power supply voltage V1
Across R-S, S-T and T-R
<Across L1-L2, L2-L3 and L3-L1>Moving-iron type AC voltmeter
Commercial power supply
Within permissible AC voltage
fluctuation Refer to Page 40
Power supply side
current I1
R, S and T line currents
<L1, L2, and L3 line currents> Moving-iron type AC ammeter
Power supply side power
P1
At R, S and T, and across R-S,
S-T and T-R
<At L1, L2 and L3, and across L1-
L2, L2-L3 and L3-L1>
Electrodynamic type single-
phase wattmeter
P1 = W11 + W12 + W13
(3-wattmeter method)
Power supply side power
factor Pf1
Calculate after measuring power supply voltage, power supply side current and power supply side power.
× 100%
3 V1I1
P1
Pf1 =
Output side voltage V2Across U-V, V-Wand W-U Rectifier type AC voltmeter
(Note 1) (Not moving-iron type)
Difference between phases is
within ±1% of maximum output
voltage.
Output side current I2U, V and W line currents Moving-iron type AC ammeter
Current should be equal to or less
than rated inverter current.
Difference between phases is 10%
or lower.
Output side power P2At U, V and W, and across U-V
and V-W
Electrodynamic type single-
phase wattmeter
P2 = W21 + W22
2-wattmeter method (or 3-
wattmeter method)
Output side power factor
Pf2
Calculate in similar manner to power supply side power factor.
× 100%
3 V2I2
P2
Pf2 =
Converter output Across P-N< Across + and - > Moving-coil type (such as
tester)
POWER lamp lit
1.35 × V1
Maximum 760V during
regenerative operation
Across 2 (+) −5 0 to 5V/0 to 10VDC
Across 1 (+) −5 0 to ±5V/0 to ±10VDCFrequency setting signal
Across 4 (+) −5 4 to 20mADC
Across 10 (+) −55VDC
Frequency setting power
supply Across 10E (+) −5 10VDC
“5” is
common.
Across FM (+) −SD
Approximately. 5VDC at
maximum frequency
(without frequency meter)
DC8V
T1
T2
Pulse width T1:
Adjusted by Pr.900
Pulse cycle T2: Set by Pr.55
(Valid for frequency
monitoring only)
Frequency meter signal
Across AM (+) −5
Approximately 10DVC at
maximum frequency
(without frequency meter)
Start signal
Select signal
Across STF, STR, RH, RM, RL,
RT, AU, STOP, CS (+) −SD
Reset Across RES (+) −SD
Output stop Across MRS (+) −SD
Moving-coil type (Tester, etc.
may be used) (Internal
resistance: 50kΩ or larger)
20 to 30VDC when open.
ON voltage: 1V or less
SD is common.
Alarm signal Across A-C
Across B-C
Moving-coil type
(such as tester)
Continuity check (Note 2)
<At OFF> <At ON>
Across A-C: Discontinuity Continuity
Across B-C: Continuity Discontinuity
Note 1. Accurate data will not be obtained by a tester.
2. When Pr. 195 "A, B, C terminal function selection" setting is positive logic.