Continental TM-40 system flag #3(kVp commutation fail error)

Trouble Shooting Guides
KV Commutation Failure
Possible
Causes:
• Arcing of x-ray tube, HV cables, or tank
• Rotor is not spinning on the selected tube
• Line voltage too high
• Line voltage mis-matched (during installation)
• Snubber board with higher inductance resistors (for generators before
March of 1994)
• Maximum frequency on the kVp Control PCB is mis-adjusted
• SCR fuse (F9) has opened during exposure (on units that have F9)
• main circuit breaker has opened during exposure (on units that employ circuit
breakers)
• damaged SCR
Things To
Check:
1. Verify that there is no carbon deposit on the HV cable connectors.
2. Make sure the HV cable connector pins make good contact.
3. Verify that the HV cables are properly clamped at the HV tank side and at
x-ray tube side. Add wavy washers, if there is any up-down or side-to-side
play.
4. SCRs for short and open
5. Inverter Power Supply on Gate Drive PCB TB5 (must be below 540 VDC)
6. Diode Pack DP6 is potentially shorted
7. T-Network mis-wired (during retrofit or repair)
8. SCR fuse fatigued (multiple HV arcing occurred for some time)
9. Snubber board for low inductance resistors
10.Damping Resistors are the proper type (OMITE) with glass-like glazing.
11.Main contactor for carbonization marks (on contactor type units)
12.Maximum frequency on the KV Control PCB= 11.0 kHz
13.Damaged impulse transformers (orange) on the Gate Drive Board.

Shawn,I've got a great contact for u, his name is Hugh Hudson he is retired from Hologic who bought out contintal,bennett and transworld. He has all his manuals at home. if u give him a P.O. he help u through it all. Nobody knows more about them. His # is 971-404-4634, he's on the west coast. u can also call Hologic at 800-343-9729 ask for jim booze but I think he learned from Hugh.good luck.