Stator Power and Control
The major components of this functional group consist of X-Ray Controller PCB, Power/Motor Relay PCB, T3 Stator Transformer,
and X-Ray Tube.
1. Operation of this group begins when you place the ON/OFF switch on the Workstation in the ON position, starting the
boot sequence.
2. Operating power becomes available at the Power/Motor Relay PCB (115VAC), and at the X-Ray Controller PCB (DC).
3. At the beginning of the boot sequence, the ARCNET data from the Workstation initializes the CPU on the X-Ray
Controller PCB. The CPU generates a signal that starts the Interlock sequence (see Interlocks in this manual).
4. When the Interlock sequence is complete, stator rotation begins, in the following sequence:
a. The X-Ray Controller PCB receives temperature status of the X-Ray tube housing and stator input voltage sense.
b. The X-Ray Controller first activates the STATOR_START signal, which switches a relay on the Power Motor Relay
PCB to select 115VAC power for the stator. It then sends a signal STATOR_RUN to the Power/Motor Relay PCB
that switches 115VAC power to the T3 Stator Transformer and to the Stator coil of the X-Ray Tube. The tube anode
begins to rotate. The return line passes through a thermal switch on the X-Ray Tube housing, that will open above
a maximum safe temperature and stop the anode from rotating.
c. After two seconds, when the anode reaches running speed, the X-Ray Controller causes the 115VAC to the stator
and capacitor to turn off by turning off the STATOR_RUN signal on the Power/Motor Relay PCB. The signal
STATOR_START is turned off 100ms later to switch 40VAC power from the T3 Stator Transformer to supply the
Stator coil of the X-Ray Tube. After 100ms, the STATOR_RUN signal is turned on again, and the stator continues
to run, powered by 40VAC instead of 115VAC. A STATOR_SENSE signal is monitored by the X-Ray Controller to
confirm that the anode is rotating (when it is not, the current drawn by the stator coil changes, so that a failure can
be detected.) If the thermal switch operates, the circuit will then shut down the system.
d. To prevent the thermal switch from operating, which should only occur as a safety measure if the tube housing
exceeds rated temperature and results in a potential oil leakage hazard, the housing temperature is monitored
continuously by the X-Ray Controller PCB. If it exceeds a certain percentage of the housing heat capacity, a
warning message will be displayed, alternating with the technique.
e. The X-Ray Controller also integrates the heat input due to every X-ray shot, and calculates the tube anode
temperature continuously. If the anode temperature exceeds a certain percentage of its capacity, a warning
message will be displayed, alternating with the technique. Beyond a higher warning level, boosted X-ray production
will be limited to avoid overheating the tube anode.
3
Service
Periodic Maintenance
Contents
Schematics
Illustrated Parts
Installation
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