Igbt Test Method; Legend Almost Infinite Resistance; Almost Zero Resistance - Hitachi X200 Series Instruction Manual

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
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.
Table Legend Almost infinite resistance:
Part DVM
+ –
D1 [R] [+1]
[+1] [R]
D2 [S] [+1]
[+1] [S]
D3 [T] [+1]
[+1] [T]
D4 [R] [–]
[–] [R]
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.
NOTE: Before measuring the voltage between [+] and [–] with the DC current range,
confirm that the smoothing capacitor is discharged fully, then execute the tests.
Measured Part DVM
Value
+ –
D5 [S] [–]
[–] [S]
0
D6 [T] [–]
[–] [T]
0
TR1 [U] [+]
[+] [U]
0
TR2 [V] [+]
0
[+] [V]
resistance range. You can check the

Almost zero resistance:

Measured Part DVM
Value
+ –
TR3 [W] [+]
0
[+] [W]
TR4 [U] [–]
0
[–] [U]
TR5 [V] [–]
[–] [V]
0
TR6 [W] [–]
0 [–] [W]
6 15
6 15
0
Measured
Value
0
0
0
0