Introduction Poor or inconsistent quality of x-ray images is often caused by inaccuracy or inconsistency of the generator’s timer. This results in repeat examinations, which cost time and money. A poorly maintained system is also a hazard to the patient; when a malfunction in the timer occurs, the patient may receive unnecessary radiation doses. It is for important reasons such as these, that regular monitoring of x-ray systems and timers is an essential part of a good quality assurance program.
Applications The Digital X-Ray Pulse Counter/Timer is a non-invasive, solid-state instrument that can be used to measure the exposure time of either AC or DC x-rays. It can also measure the duration of radiation output produced by a wide variety of medical and dental x-ray systems. A sensitive x-ray detector in the instrument allows direct measurement of exposure from the x-ray head. Pulses produced by half-wave and full-wave x-rays are measured as 60 or 120 pulses per second. For DC, capacitor discharge and three-phase x-rays, the Digital X-Ray Pulse Counter/Timer measures the exposure time in milliseconds. When testing x-ray timers and controls, the time of relay contact closure can be measured using the AC input feature.
An output connector on the side of the Digital X-Ray Pulse Counter/Timer allows the user to view a radiation output waveform on an oscilloscope. Using this feature, technicians can diagnose and troubleshoot problems with x-ray generators.
Features
Measures duration of radiation output produced by x-ray generators
Measures AC or DC x-rays
Gives direct readings (time or pulses)
Can be used for medical or dental x-ray systems
Designed specifically to allow service personnel to accurately and easily assess the performance of x-ray generators, timers, and controls
Saves time and money by reducing repeat examinations
Easy-to-read digital display
Automatic reset; holds a reading until the next exposure
Battery-operated, lightweight; fits easily into tool box or pocket
Output connector (included) allows a radiation output waveform to be viewed on an oscilloscope
For added operator convenience, the remote sensor is available as an option
Product Specifications
Accuracy
AC input ± 1 count, DC input 2 %, ± 1 count, X-ray detection ± 1 count
Sensitivity
AC input 90 VAC minimum X-ray input 50 kVp, 5 mA at 5 cm from top surface of case, pointed to target on case
Range
9999 pulses; 9999 ms
Display
0.3 inch liquid crystal
Power requirements
9 V battery, alkaline or equivalent, 48 hours minimum; typically 6 months of normal use
AC input jacks
130 VAC maximum; 90 VAC minimum; input circuit not affected by reversed polarity
Output signal
BNC connector for waveform analysis
Connections
None required for direct exposure measurement
Controls/Indicators
•Three-position switch: Pulse, Off, Milliseconds • Four-digit LCD (0.4 inch character) • Low battery indicator •“Low Batt” appears in display when battery voltage reaches 5.3 V ± 0.3 V • Power-on: LED (green); oscilloscope output
Remote sensor
The optional remote sensor can be used when the user would like to have the unit in their hand, so that readings can be seen without having to walk back-and-forth from the x-ray table to the control room after each exposure. The remote sensor can also be used when placement of the Digital X-Ray Pulse Counter/Timer in the beam is questionable, such as in a Panorex dental x-ray unit
