Diagnostic X-ray appts with exposure control - has switch shunted by high resistance in series with triac shunted by capacitor

摘要

The diagnostic X-ray apparatus is so designed that voltage peaks from the HV transformer cannot result in any undesirable firing of the triacs, nor can a defective triac cause X-rays to appear when the supply voltage fluctuates. The triac which switches the primary winding of the HV transformer for the X-ray tube has its gate connected to an mAs relay. An exposure trigger closes the switch, which is shunted by a 5 600 ohm resistor, as it actuates the relay to produce a firing voltage for the triac. A capacitor and a resistor across the triac reduce the inductive voltage peaks when the switch cuts in the primary winding.