PCM-2 Manual.pdf - Voss Associates

Section 1
()ducti n
General Description
The Eberline model PCM-2 is a monitoring instrument which provides rapid and
convenient detection and localization of alpha and beta/gamma contamination on
persoill1el. Sixteen (16) gas proportional detectors, designed for rapid replacement
and/or repair, provide superior localization of contamination and background
rejection. A contoured array of 34 counting zones, each with separate alpha and
beta/gamma channels, provides data from which the instrument can determine the
presence of both localized and distributed contamination. In addition, up to 75
"Sum Zones" can be defined, each comprised of 2,3 or 4 adjacent detectors,for a
maximum detection of contamination that is spread over two or more detectors.
A "Sum Channel" is the summation of all 34 detectors into a single counting
channel. With ex and i3/'Y discrimination, the 34 discrete channels, 75 Sum Zones,
and the Sum Charmel provide a total of 220 measurements per count cycle. Since
a person is measured with two count cycles, there are 440 independent
measurements performed per person. The"Sum Channel" is thereby capable of
detecting low-level, widely-distributed contamination.
Individual detector channels within the PCM-2 are independently controlled by
distributed microprocessors. In addition, a 20 Mhz 80386SX based computer is
built in to provide a user-friendly interface for the system. This enhanced
controller also simplifies calibration and maintenance of the unit and presents test
results to the user in a clear and easily understood graphic format. A full-size
keyboard is stored internal to the unit for use during setup, calibration and
troubleshooting. The PCM-2 is also capable of logging measurement data in any
of several formats to a printer and/or host computer system.
The PCM-2 features an functionally ergonomic design which maximizes user body
contact and minimizes dead areas between detectors. A color VGA monitor is
used to display information during normal operation as well as during setup,
calibration and maintenance. If contamination is defected during a measurement
cycle a color graphic image is presented to indicate contamination location(s).
PCM2.MANI REV AI April 1995
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