Chapter 8 - Troubleshooting & Maintenance
8-4
Check diodes in the rectifier bridge and IGBT module with multimeter in the sequence shown in
below table and diagram. Diode state codes: C- Closed and O- Open.
8.4.2 Diode Bridge and IGBT Module Test for 50~700HP VFDs
Before checking the power components, disconnect AC input power and wait for about 10 minutes.
Check that there is no DC voltage on P1+ and N- terminals.
Disconnect power wires from R, S, and T terminals and motor leads from U, V, and W terminals.
Check diodes in the rectifier bridge and IGBT module with multimeter in the sequence shown in
below table and diagram. Diode state codes: C- Closed and O- Open.
Note: The 50-700HP VFDs have half controlled rectifier bridge with SCRs (silicon controlled rectifier).
The SCR cannot be checked for open state with multimeter. The reading from R to P1 terminals will
represent charge diode and resistor circuit. Terminals S and T to P1 will show closed state in direct and
reverse test if SCRs are not shorted.
Black
Lead to
P1+
Black
to
N
Red
to
P1+
Red
to
N
Red
to
R
S
T
R
S
T
Black
to
R
S
T
R
S
T
State
O
O
O
C
C
C
State
C
C
C
O
O
O
Red
to
U
V
W
U
V
W Black
to
U
V
W
U
V
W
State
O
O
O
C
C
C
State
C
C
C
O
O
O
Charge
Resistor
M/C Contact
R
S
T
U
V
W
+
+
+
+
DC Bus
Capacitors
DC Bus Positive
(P1+)
(N-)
DC Bus Negative
IGBT transistors
Six- Pulse
Rectifier Bridge
Charge Diode and Resistor
SCRs
DIODES
R
S
T
U
V
W
+
+
+
+
DC Bus
Capacitors
DC Bus Positive
(P1+)
(N-)
DC Bus Negative
IGBT transistors
Содержание CI-007-P2
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Страница 109: ...Chapter 6 Parameter Description 7 2 7 3 PID control Sleep mode with Sleep Pressure Boost function diagram...
Страница 110: ...Chapter 6 Parameter Description 7 4 PID control with Pipe Broken function diagram...
Страница 111: ...Chapter 6 Parameter Description 7 4 7 5 PID control with Pre PID function diagram...
Страница 112: ...Chapter 6 Parameter Description 7 5 7 6 PID Control Setting Notes...
Страница 113: ......
Страница 126: ...Chapter 9 Options 9 7 Conduit box for 030 040HP VFD Conduit box for 050 075HP VFD Conduit box for 100 125HP VFD...
