Ch 6. Circuit & Heat Mgmnt Flashcards
L.V.C
H.V.C
Filament circuit
Each contains a specific transformer
3 sections of the X-ray circuit
between the AC power supply & the primary side of the high voltage (S.U.T)
Low voltage circuit
-Technique selectors
-autotransformer
-exposure switch & timer
-main switch
components located in the control console
single coil transformer with 3 functions:
- provides kVp selection
- provides compensation for fluctuations of incoming voltage
- supplies power to other circuits
autotransformer
Primary purpose: vary voltage to the primary side of the S.U.T
Autotransformer purpose
closes circuit to allow current flow to primary side of S.U.T
exposure switch
Terminates exposure & is set on control console
Exposure Timer
Begins & ends on the secondary side of the S.U.T; includes:
- tube & rectifier unit
- current only flows in this circuit during exposure
High Voltage Circuit
PRIMARY PURPOSE: supply the tube with enough voltage to create xrays
high voltage circuit’s primary purpose
divided into 2 parts by the S.D.T
- activated anytime mA is adjusted
Filament Circuit
PRIMARY PURPOSE: supply low current to heat tube filament for thermionic emission
Filament Circuit’s Purpose
changes AC to DC by using a diode
Rectification
device that makes current flow in one direction
Diode
Self-rectification: not used
Half-wave: 2 diodes; 60p/s; prevents “backflow” eliminating negative half of cycle
Full-Wave: 4 diodes; 120p/s; “redirect” current to have both pos. & Neg. flow in same direction
3 types of rectification
Power comes from a single source of AC = a pulsating beam
- lowest power
- least expensive
single-phase generator
