Yaskawa VCD 723 - Manual (Page 71)

4 Troubleshooting/Maintenance
65 Troubleshooting Flowcharts
9/15/93
Chart 6. Blown Fuse ( FU ) Fault Indication
WARNING
DO NOT REPLACE DC BUS FUSE WITHOUT
FIRST CHECKING OUTPUT TRANSISTORS.
DISCONNECT LEADS FROM
OUTPUT TERMINALS
T1(U), T2(V) AND T3(W).
ARE MOTOR WINDINGS
SHORTED (T1 TO T2,
T2 TO T3, OR T3 TO T1)?
MOTOR
IS FAULTY.
LOCATE AND
REMOVE SHORT.
REPLACE
DAMAGED POWER
TRANSISTORS.
YES
YES
YES
NO
NO
NO
ARE VCD 723 PHASES
SHORTED TO GROUND?
T1(U), T2(V), T3(W)
TO G(E).
CHECK POWER TRANSISTORS
(SEE TABLE 10).
ARE TRANSISTORS
DAMAGED?
DRIVE
IS FAULTY.