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Models 375-31H Area Monitor with Neutron Detector
Section 3
Ludlum Measurements, Inc.
Page 3-2
January 2021
DET Fail
: indicated by a red light and an audible tone greater than 68 dB
at 6.1 ft (2 m) for conditions of detector overload, no count from
detector or instrument failure
Low Bat
: indicated by a yellow light, beginning when two hours of
battery life remain
Connector
: series
˝
C
˝
(others available)
Ethernet (optional):
10 Base-T connection for use with Ludlum software
Calibration Controls
: accessible from the front of instrument (protective
cover provided)
High Voltage
: adjustable from 450-2500 volts
Dead Time
: adjustable to compensate for dead time of the detector and
electronics (can be read on the display)
Overload
: a display reading of -OL- and audible
FAIL
alarm indicate
detector saturation. It is normally set to initiate just above the highest
range of the detector.
Over-range
: A display reading of
˝----˝
and activated low and high alarms
indicate that the radiation field being measured has exceeded the counting
range of the instrument (or when dead time correction accounts for more
than 75% of the displayed reading).
Data Output
: A 9-pin connector with female sockets provides five-
decade log output, RS-232 output, signal ground connection,
FAIL
and
HIGH ALARM
signals (current sink), and direct connection to battery and
ground