Section 5: Troubleshooting
5.4 Troubleshooting Procedures
0101-8292-0, Rev. C
5-15
CV-12SLX User Manual
Ishikawa Diagram #17: Emission Current Unstable
5.4 Troubleshooting Procedures
5.4.1 Checkout of HV Circuit and Cable Connections
Before performing procedures described in Tables 5-5, 5-6, and 5-8 through 5-21,
perform the following procedure to verify the integrity of the HV circuit and the
power supply’s cable connections. Follow all safety procedures described in the e-
beam gun manual.
Step
Action
1
Vent the vacuum system to atmosphere and lower the source tray.
2
Touch a properly installed grounding hook to the e-beam gun’s emitter, to
the HV feedthroughs, and to the source tray.
3
Check the emitter assembly, the HV leads, the HV feedthroughs, and the
source tray for flakes and debris and clean as necessary.
4
Check the emitter’s filament for breaks and replace if necessary.
5
Check the emitter assembly, the HV leads, the HV feedthroughs, and the
atmosphere side HV cables for possible shorts. Correct any shorts found.
6
Check all cable interconnections between components of the power supply
and between the power supply and the vacuum system. Verify that all
connections are correctly and securely made.
HVPS A3 HV
Regulator PCB
HVPS A2 HV
Output PCB
Damaged emitter
HVPS mA
Feedback
Defective A2 HV
Output PCB
Defective feedback cable or connection
A2J5 to A3J12 connection
Consequence
Possible Causes
Emission Current Unstable
Faulty/loose connections in
HV path or output path
Defective A2 HV Output PCB
R4/R5 100 Ohm resistors
HV feedthrough
shorted/damaged