Thermal Arc 300GTSW Pro-Wave, Service Manual

Page: 68 / 130

pro-wave 300gtsw
6-30
June 21, 2012
6.28 PCA IGBT Inverter Q3/Q4
Replacement Procedure
Refer to figure 6-27.
to remove IgBt Inverters Q3/Q4, do the following.
1. Remove the Output Inductor Assembly refer to
the section further in Advanced Troubleshooting.
2. Remove the Output Bus Bar/CT Assembly by
removing the bolt inside the POSITIVE (+)
OUTPUT TERMINAL and the two screws on the
terminals of Q3/Q4 holding the Output Bus Bar/
IGBT Inverter bus bar to IGBT Inverter.
3. Disconnect the lugged wires at terminals AC1 and
AC2 on the HF Unit.
4. Disconnect connector CN1 on IGBT Inverter Q3/
Q4.
5. Remove the four (4) screws securing Q3/Q4 to
the chassis.
to replace either Inverter Q3/Q4, do the following:
1. Spread a light coating of thermal compound on
the bottom surface of the Inverters.
2. Reverse the remaining removal steps above. When
replacing the screws that secure the Inverter to the
chassis, make sure all screws are started before
tightening them. It may be helpful to connect CN2
and CN5 before seating the board fully onto the
chassis.
IGBT Inverter Q3 Junction Hardware
Bolt, Positive (+) Output
Current Transformer Output Bus Bar
Art # A-06124
Figure 6-27: IGBT Inverter Q3