APX 525/625 Generator Revision C Diagnostics
©
2005 Del Medical Imaging Corporation
7/5/2005 Page 165
closed with a jumper wire. This jumps out the “Bucky in Motion” switch and enables
the start of the exposure.
Is the F1 fuse for the inverter DC supply open?
Caution: Dangerously high voltages may be present on the filter capacitors after
power to the generator is turned off. Always check the DC supply to the inverter with
a voltmeter before checking the F1 fuse or components in the inverter assembly.
Check the F1 fuse for continuity. Before replacing the fuse, check the inverter
components for visible signs of damage, such as charring or loose connections.
Check for shorted SCRs, diodes, or other RC snubber components.
The blown F1 fuse could be caused by any of the following conditions:
• Break in the primary circuit to the high voltage transformer (e.g.: a bad
connection or incorrect wiring)
• Short in the primary circuit to the high voltage transformer (perhaps
shorted to ground, e.g. the primary connection cover or incorrect
wiring)
• Short in the inverter (e.g.: a shorted SCR)
• Short (arcing) in the secondary, HV Cables or X-Ray tube
• Line Voltage Drop (consult the power requirements documentation)
• Gross maladjustment of the filament pre heat
• Gross maladjustment of the SCR hold off adjustment
kV FAULTS
For these generators, a text statement in the display and an early or instantaneous
termination of exposure indicates a kV Fault.
Turn the unit off then back on to reset the generator and clear the fault message
from the display.
The kV Fault signal originates on the kV Regulator Board, in a circuit that monitors
the actual kV feedback. This circuit uses two sets of window comparators to watch
the anode and cathode feedback signals separately.
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