Nt1310 Final Exam
1. List the components of the x-ray generating system and the primary functions of each. a. Line compensator- measures the voltage provided to the x-ray imaging system and adjust that voltage to precisely 220 V. input voltage can vary up to 5%. b. Autotransformer- is designed to supply precise voltage to the primary side of high voltage transformer and to the filament circuit. c. kVp controls- by selecting the major or minor kVp controls, a more precise kilovolt peak is provided. kVp major changes secondary side connection on autotransformer to 10-20 turns. kVp minor changes secondary side connection on autotransformer to 1-2 turns. The kVp meter connected to the output terminals of the autotransformer reads voltage not kV. The pre-reading meter voltage is also monitored continuously.
…show more content…
mA controls- mA is the number of electrons crossing from cathode to anode (tube current). It is determined by the filament temperature. Filament temperature is controlled by the filament current. As the temperature increases, thermionic emission increases. The tube current is controlled by the filament circuit which the connection on the autotransformer provides voltage to the filament circuit. The mA selector is a resistor bank or rheostat (variable resistor). This transformer increases or decreases voltage. e. Filament Transformer- a step down transformer that is located between mA selector and filament. It increases the current to heat the filament and decrease voltage. The mA selector provides precise current to the step down transformer. f. Exposure timers- a timer circuit on the primary side of high voltage transformers. There are 4 types that are controlled by the technologist the mechanical; synchronous- timed off of # of cycles; electric- can do less than 1/60 s; mAs- on secondary side of high voltage transformer. There is one that is automatic, the AEC (phototimer) which selects the
mA controls- mA is the number of electrons crossing from cathode to anode (tube current). It is determined by the filament temperature. Filament temperature is controlled by the filament current. As the temperature increases, thermionic emission increases. The tube current is controlled by the filament circuit which the connection on the autotransformer provides voltage to the filament circuit. The mA selector is a resistor bank or rheostat (variable resistor). This transformer increases or decreases voltage. e. Filament Transformer- a step down transformer that is located between mA selector and filament. It increases the current to heat the filament and decrease voltage. The mA selector provides precise current to the step down transformer. f. Exposure timers- a timer circuit on the primary side of high voltage transformers. There are 4 types that are controlled by the technologist the mechanical; synchronous- timed off of # of cycles; electric- can do less than 1/60 s; mAs- on secondary side of high voltage transformer. There is one that is automatic, the AEC (phototimer) which selects the