Ludlum Model 375/4

   Digital Area Radiation Monitor (1 mR/hr - 10 R/hr)

Features

• Affordable Area Radiation Monitor

• Built-In Energy Compensated G-M Radiation Detector

• Detection Range from 1 mR/hr - 4 R/hr

• Compact, Integrated Design

• Battery Backup

• Networkable

• Audio and Visual Alarms

• Optional Remote

• Detector Fail Indicator

• Data Output/RS-232

Introduction

The Ludlum Model 375/4 Digital Wall-Mount Area Radiation Monitor is designed for visibility and ease of use. This monitor incorporates an internally housed energy compensated G-M radiation detector with a range from 1 mR/hr to 10 R/hr. Featuring a wall-mount chassis, and has a four-digit LED display that is readable from thirty feet away. Backlit indicators warn of low radiation alarm (yellow), high radiation alarm (red), instrument failure (red) and low battery (yellow). A green status light is a positive indication of instrument operation. Parameters are protected under a calibration cover. Calibration is easily accomplished by moving the cal dipswitch to the right, and using the pushbuttons to increment or decrement the calibration constant, dead time correction and alarm point parameters. Parameters are stored in non-volatile memory (retained even with power disconnected). A five-decade logarithmic analog output is provided. It additionally has a 48 hour battery backup to keep the system operational in the event power is lost. 

Specifications

PART NUMBER: 48-2411

INDICATED USE: Area radiation monitoring
COMPATIBLE RADIATION DETECTORS:  Internally mounted energy compensated G-M
RANGE: 1 mR/hr - 10 R/hr

DISPLAY: 4 digit LED display with 0.8" (2 cm) digits
DISPLAY RANGE: 000.0 - 9999
DISPLAY UNITS: Can be made to display in μR/hr, mR/hr, R/hr, μSv/hr, mSv/hr, Sv/hr, μrem/hr, mrem/hr, rem/hr, cpm, cps, and others
LINEARITY: Reading within 10% of true value
RESPONSE: Typically 3 seconds from 10% - 90% of final reading
STATUS: Green light, instrument functioning properly
ALARMS:

A. Low Alarm: Yellow light, 1 beep/second audible, selectable range: 0-9999
B. High Alarm: Red light, 4 beeps/second audible, selectable range: 0-9999
C. Detector Fail: Red light, constant audible tome > 68 dB at 2 feet
D. Low Bat: Yellow light, indicates less than 2 hours of battery life remaining
HIGH VOLTAGE: Adjustable from 200 - 2500 volts
THRESHOLD: Adjustable from 2 - 100 mV
DEAD TIME: Adjustable to compensate for dead time of detector and electronics (can be read on display)
OVERLOAD: Senses detector saturation (indicated by display reading “-OL-”)
OVERRANGE: Indicates radiation field being measured has exceeded counting range of instrument (indicated by display reading “– – – –”)
DATA OUTPUT: 9 pin connector providing 5 decade logarithmic output, RS-232 output, signal ground connection, FAIL and ALARM signals (current sink), and direct connection to battery and ground
CALIBRATION CONTROLS: Accessible from front of instrument (protective cover provided)
POWER: 95 - 135 Vac (178 - 240 Vac available), 50-60 Hz single phase. 6 volt sealed lead-acid rechargeable battery (built in)
BATTERY LIFE: Typically 48 hours in non-alarm condition; 12 hours in alarm condition
BATTERY CHARGER: Battery is continuously trickle charged when instrument is connected to line power and turned on

REMOTE (optional): Model 271, Model 272, Model 272D
CONSTRUCTION: Wall mount aluminum housing with ivory powder coat paint
SIZE: 7.4” H x 9.7” W x 2.5” D (18.7 x 24.6 x 6.4 cm)
WEIGHT: 6.5 lbs. (2.3 kg)

This Product is CE Certified

Options

Technical Information

• Model 375/4 Manual

• Model 375/4 CE Certificate

• Model 375 Network Setting Request Form

Other Ludlum Products

• Other Ludlum Products

Ludlum Information

• Ludlum Introduction

• Ludlum Resources

• Ludlum Warranty

• Ludlum Repair and Calibration

• Ludlum Training