OEC 9800C-Arm, Service Manual, Page: 130 / 490

X-ray On, X-ray Disable
Circuit/Mechanical Descriptions
The X-ray On Switch located on top of the Cross Arm cover sends an enable signal through the Power/Signal Interface PCB to
the X-ray Controller PCB to initiate an x-ray exposure. The X-ray Lamp lights when an exposure occurs.
The X-ray Controller PCB is the interface for the Generator subsystem to the ARCNET for control of X-ray generation and also
enables the status display on the C-Arm Control Panels and Workstation monitors. The PCB controls kV and mA generation and
regulation. The PCB also interfaces to the Handswitch and Footswitch.
The Fast Stop switches are located on the rear of the Cross-Arm Side Cover and are connected to the Power/Signal Interface
PCB. One set of the dual contacts of each switch removes power from the tube stator transformer and software immediately
stops x-rays. The other contact set r24VDC power from the vertical column motor K15 and K16 relays to prevent
motorized mechanical motion.
An HLF or FLUORO Footswitch command goes through an opto-isolator to the microprocessor on the X-ray Controller PCB.
This MODE switch command is also input to the X-ray Controller PCB and communicated to the Workstation via ARCNET.
The SECURITY line from the Footswitch or Handswitch is output from the X-ray Controller PCB as the X-ray Enable signal line to
the HV Supply Regulator PCB. A low on this signal line provides a shutdown capability via PWM U12 on this PCB. The shutdown
occurs when all PWM driver outputs to the Generator Driver PCB are asserted low.
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Service Periodic Maintenance Contents Schematics Illustrated Parts Installation