X-ray Imaging System Flashcards
Sections of the x-ray machine circuitry
Primary side (low voltage) or control console/panel
Secondary side (high voltage)
Filament circuit (low current
Three main components of x-ray imaging system
X-ray tube
Operating/control console
High voltage generator
Primary side (low voltage or control console) parts are:
Main breaker
Exposure switch
Autotransformer
Timer circuit
Filament circuit parts are:
Filament circuit variable resistor
Filament step-down transformer
Secondary (high voltage side) parts are
High voltage step-up transformer
Four-diode rectification circuit
X-ray tube
Rotor stator
Operating/control console is used to control the:
Voltage applied to the x-ray tube
Current through the x-ray tube
Exposure time
Autotransformer has single winding and is designed to supply a precise voltage TO:
To the filament circuit
To the high voltage circuit
Formula of autotransformer law
Vs/Vp = Ns/Np
What are the 4 basic exposure timers
Mechanical Timer
Synchronous Timer
Electronic Timer
mAs Timer
Current and Turns ratio formula
Ip/Is = Ns/Np
Most familiar with radiologic technologists
Operating/control console
Allows radiologic technologist to control the x-ray tube
Operating/control console
Contain the operator console and technique charts and space to store cassettes
Control booth
Wall bet. the booth and x-ray unit is shielded with
Lead
Provided for monitoring kVp mA and exposure time
Meters
Connecting to the meters are at low voltage to minimize electric shock
Electric circuits
Makes incoming voltage uniform or smooth
Automatic line compensator or
LVC line voltage compensator
Measure the voltage provided to x-ray imaging system and adjust that voltage to precisely 200V
Automatic line compensator or
LVC line voltage compensator
Power supplied to the x-ray imaging system is first delivered to the
Autotransformer
Determines voltage to step-up transformer
Autotransformer
In series with the timer
Exposure switch
AKA dead man switch
Exposure switch
It is automatically terminates the exposure when the finger ceases to press on the timer button
Exposure switch
Device used to control the length of x-ray
Exposure timers
In older x-ray equipment small portable and dental sets had CLOCKWORK timer
Mechanical Timer
These type of mechanical timers have a ELECTRIC motor called synchronous motor which is accurate than CLOCKWORK TIMER
Synchronous Timer
Most sophisticated most complicated most accurate x-ray exposure timer
Electronic timer
Allow wide range of time interval to be selected and are accurate to intervals as small as 1ms
Electronic timer
Monitors the product of mA and exposure time and terminates exposure when the desired mAs value is attained
mAs timer
Designed to provide the highest safe tube current for the shortest exposure for any mAs selected
mAs timer
Filament Transformer also known as
Filament heating isolation step-down transformer
