The Method To Check Inverter, Converter Part - Hitachi L300P-110L Instruction Manual

5.5 The method to check Inverter, converter part

A test is possible to check quality.
(Preparation)
[1] Take out the power lines (R, S and T) connected to the inverter, the motor connection lines (U, V and
W) and the regenerative control resistance (P and RB).
[2] Prepare tester. (Using range of 1 ohm resistance measure range.)
(How to check)
It is possible to check the quality of the charging state of the terminals R, S, T, U, V, W, RB, P and N of
the inverter and the pole of the tester by measuring the charging state.
(Note 1) Before you measure the voltage between P and N with DC current range, confirm that the
smoothing capacitor is discharged fully, execute checks.
(Note 2) Almost infinite value is indicated on no conducting.
With the effect of the smoothing capacitor, the inverter conducts instantly and an infinite value isn't
indicated. Ohm-number 10 ohms is indicated on conducting.
The values indicated will not be exactly the same for each terminal, however they will be very close
together. If there is a significant difference a problem may exist.
Pole of tester
(Red) (Black)
D1 R PD
PD R
D2 S PD
PD S
D3 T PD
PD T
D4 R N
N R
D5 S N
N S
D6 T N
N T
TR1 U P
P U
TR2 V P
P V
TR3 W P
P W
TR4 U N
N U
TR5 V N
N V
TR6 W N
N W
TR7 RB P
P RB
RB N
N RB
Measure
value
Converter
No-conduct
Conduct
D1
No-conduct
Conduct
R
No-conduct
Conduct
S
Conduct
No-conduct
T
Conduct
No-conduct
Conduct
D4
No-conduct
No-conduct
Conduct
No-conduct
Conduct
No-conduct
Conduct
Conduct
No-conduct
Conduct
No-conduct
Conduct
No-conduct
No-conduct
Conduct
No-conduct
No-conduct
5-4
Chapter 5 Maintenance, Inspection
PD P RB
D2 D3
C +
TR7
D5 D6
N
Inverter
TR1 TR2 TR3
TR4 TR5 TR6
U
V
W