Yaskawa GPD 506/P5 Section One - Manual (Page 30)

PP.P5G5.01.Troubleshoot
Page 30
Rev. 06/11/2003
DC Bus Fuse
for models 2030 through 2075 and 4055 through 4160
Some larger models employ three DC bus fuses instead of one. If the DC bus fuse(s) are open, at
least one of the output transistors has failed. When a transistor fails, there is a short between the
positive and negative portions of the DC bus. Again, the DC bus fuse(s) do not protect the
transistors, but protects the rest of the main circuit from the high current present during a short.
Never replace the DC bus fuse (s) without first checking all of the output transistors.
Caution: If the DC bus fuse(s) are replaced without replacing the shorted output transistor, non-
warranty damage will occur.
M
L1
L2
L3
(+)
(-)
T1 T2 T3
FU1 FU2 FU3
Main Circuit Diagram