Hitachi L100 Manuel D’Utilisation
L100 Inverter
T
roub
leshooting
and Maintenance
6–15
IGBT Test Method
The following procedure will check the inverter transistors (IGBTs) and diodes:
1. Disconnect input power to terminals [R, S, and T] and motor terminals [U, V, and W].
2. Disconnect any wires from terminals [+] and [–] for regenerative braking.
3. Use a Digital Volt Meter (DVM) and set it for 1
Ω resistance range. You can check the
status of the charging state of terminals [R, S, T, U, V, W, +, and –] of the inverter and
the probe of the DVM by measuring the charging state.
the probe of the DVM by measuring the charging state.
Table Legend – Almost infinite resistance:
≅ ∞ Ω Almost zero resistance: ≅ 0 Ω
NOTE: The resistance values for the diodes or the transistors will not be exactly the
same, but they will be close. If you find a significance difference, a problem may exist.
same, but they will be close. If you find a significance difference, a problem may exist.
NOTE: Before measuring the voltage between [+] and [–] with the DC current range,
confirm that the smoothing capacitor is discharged fully, then execute the tests.
confirm that the smoothing capacitor is discharged fully, then execute the tests.
Part
DVM
Measured
Value
Part
DVM
Measured
Value
Part
DVM
Measured
Value
+
–
+
–
+
–
D1
[R]
+1
≅ ∞ Ω
D5
[S]
[N]
≅ 0 Ω
TR4
[U]
[–]
≅ 0 Ω
+1
[R]
≅ 0 Ω
[N]
[S]
≅ ∞ Ω
[–]
[U]
≅ ∞ Ω
D2
[S]
+1
≅ ∞ Ω
D6
[T]
[N]
≅ 0 Ω
TR5
[V]
[–]
≅ 0 Ω
+1
[S]
≅ 0 Ω
[N]
[T]
≅ ∞ Ω
[–]
[V]
≅ ∞ Ω
D3
[T]
+1
≅ ∞ Ω
TR1
[U]
[+]
≅ ∞ Ω
TR6
[W]
[–]
≅ 0 Ω
+1
[T]
≅ 0 Ω
[+]
[U]
≅ 0 Ω
[–]
[W]
≅ ∞ Ω
D4
[R]
[N]
≅ 0 Ω
TR2
[V]
[+]
≅ ∞ Ω
TR7
[RB]
[+]
≅ 0 Ω
[N]
[R]
≅ ∞ Ω
[+]
[V]
≅ 0 Ω
[+]
[RB]
≅ ∞ Ω
TR3
[W]
[+]
≅ ∞ Ω
[RB]
[–]
≅ 0 Ω
[+]
[W]
≅ 0 Ω
[–]
[RB]
≅ 0 Ω
[R]
[S]
[T]
TR1
TR2
TR3
[U]
[V]
[W]
[–]
D1
D2
D3
D4
D5
D6
+
[+]
[+1]
TR4
TR5
TR6