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4.0 DESCRIPTION OF OPERATION
The block diagram below illustrates how the XRS4 functions. The following sequence of events takes place each
time the XRS4 is fired:
1. User initiates operation of the machine.
2. The control section sends a signal to the converter section to begin oscillating.
3. Once oscillating, the converter section changes the 18 volts DC to 22Khz AC.
4. The transformer charges the High Voltage Capacitor to about 10,000 volts.
5. The spark gap arcs after the High Voltage Capacitor reaches proper voltage.
6. The pulse detector signals the control block that the unit has pulsed.
7. As the High Voltage Switch is closed, a high voltage transient of approximately 370,000 volts and
10 nanoseconds in duration is applied across the X-ray tube generating X-rays.
The closing of the High Voltage Switch produces an audible pulsing sound. The XRS4 cannot produce x-rays with-
out the pulsing sound so it serves as an additional warning the XRS4 is functioning.
This unit generates X-rays through high voltage bombardment of a tungsten target.
The XRS4 does not contain ra-
dioactive materials
. All the high voltage is contained within the aluminum canister and as long as the canister is not
punctured the operator is not exposed to dangerous voltages.
BLOCK DIAGRAM
PULSE DETECTOR
USER INTERFACE
X-RAY TUBE
HIGH VOLTAGE
CAPACITOR
CONVERTER
BATTERY
SPARK GAP
CONTROLLER
