Menu
  • Home
  • Products
    • All Products
    • Health Physics
    • Medical Physics
    • Metal Recycling
    • Monitoring Systems
    • Emergency Response
    • How To Order
    • Connector Types
  • Support
    • Service Center
    • Training
    • Product Videos
    • Webinars
    • Software & Firmware Downloads
    • Rad Pro Calculator
    • Warranty Plans
    • Radiation Resources
    • Field Service Support
  • Documents
    • Product Manuals
    • Detector Reference Chart
    • Response Curves
    • Test Reports
    • Newsletter Archive
    • Technical Articles
    • End User Statement Form
    • Price List
  • Company
    • About Us
    • Ludlum Family of Companies
    • Directions to Facilities
    • Exhibition Schedule
    • ISO 9001 Certificate
    • ISO/IEC 17025 Accredited
    • Radioactive Material Licenses
    • Mobile App Privacy Policy
    • Sales Tax Business Licences
    • Terms & Conditions
    • Export Information
    • Ethics Policies
  • Careers
  • Contact Us
    • Ludlum Headquarters
    • U.S. Contacts
    • International Contacts
    • Sales Contact Form
    • Feedback Form
Ludlum Measurements Logo
(800) 622-0828 (US, CA)
(325) 235-5494
(325) 235-4672



Field Service Support

To search products by model number, enter "m..."
(Ex: Enter "m3" to search for Model 3.)

  • Home
  • Products
    • All Products
    • Health Physics
    • Medical Physics
    • Metal Recycling
    • Monitoring Systems
    • Emergency Response
    • How To Order
    • Connector Types
  • Support
    • Service Center
    • Training
    • Product Videos
    • Webinars
    • Software & Firmware Downloads
    • Rad Pro Calculator
    • Warranty Plans
    • Radiation Resources
    • Field Service Support
  • Documents
    • Product Manuals
    • Detector Reference Chart
    • Response Curves
    • Test Reports
    • Newsletter Archive
    • Technical Articles
    • End User Statement Form
    • Price List
  • Company
    • About Us
    • Ludlum Family of Companies
    • Directions to Facilities
    • Exhibition Schedule
    • ISO 9001 Certificate
    • ISO/IEC 17025 Accredited
    • Radioactive Material Licenses
    • Mobile App Privacy Policy
    • Sales Tax Business Licences
    • Terms & Conditions
    • Export Information
    • Ethics Policies
  • Careers
  • Contact Us
    • Ludlum Headquarters
    • U.S. Contacts
    • International Contacts
    • Sales Contact Form
    • Feedback Form
Health Physics Medical Physics Metal Recycling Monitoring SystemsEmergency Response

Metal Recycling

Scrap Monitoring Systems

No subcategories

Slug Sample Monitors

No subcategories

microR / microSv Meters

No subcategories

Extended Reach microR / microSv Meters

No subcategories

Isotope Identifiers

No subcategories

Need Help?

Unsure about which instrument is best for your application?

Find your region's Ludlum representative or dealer.

  • US Contacts
  • International Contacts

OR

Contact Ludlum Sales:

(800) 622-0828 (USA Toll Free)

(325) 235-5494

Newsletter

Subscribe to our customer newsletter! Stay informed about Ludlum products and services, and get helpful support tips.

Please enable the javascript to submit this form

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

m375-face-for-slash2--slash4_d_500px

Model 375/1

Digital Area Monitor

Part Number: 48-3831

Features

  • Affordable Area Monitor
  • Range: 0.1 to 9999 µR/hr
  • Compact, Integrated Design
  • Low Background Sensitivity
  • Audio & Visual Alarms
  • Networkable (Requires Ethernet or Webpage Interface Option)

The Model 375/1 Digital Wall-Mount Area Monitor is designed for visibility and ease of use. This monitor incorporates an internally housed 18 mm CsI scintillator with a sensitivity of approximately 120 cpm per µR/hr. It features a wall-mount chassis and a four-digit LED display that is readable from 9 meters (30 feet) away. Backlit indicators warn of low radiation (yellow), high radiation (red), instrument failure (red), and low battery (yellow), along with an alarm. A green status light indicates the instrument is functioning properly.

Parameters are protected under a calibration cover that provide access to adjusting 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.

Options available include remote displays, an Ethernet port, alarm relay output, and a NEMA 4 outdoor enclosure.

Note: While the detector used in this instrument is sensitive and is often used for detection of near-background levels of radiation, its nonlinear energy response means that does and exposure measurements may be over/underreported.

 

  • Specifications
  • Graphs
  • Options
  • Documents
  • Specifications
  • Graphs
  • Options
  • Documents

Specifications

Detector 18 mm CsI detector (nonlinear energy response, see Energy Response Curve in the Graphs tab)
Sensitivity 120 cpm per µR/hr
Measurement Range 0.1 to 9999 µR/hr (alternately 0.01 to 99.99 mR/hr)
Display 4-digit LED display with 2 cm (0.8 in.) characters
Display Units µR/hr (other units available upon request)
Status Indicators
  • Instrument Status: Green light indicates instrument is functioning properly
  • Low Alarm: Yellow light and slow beep (1/sec) audible tone (can be set at any point from 0.0 to 9999)
  • High Alarm: Red light and fast beep (4/sec) audible tone (can be set at any point from 0.0 to 9999)
  • Overload: Senses detector saturation (indicated by display reading “-OL-”)
  • Overrange: Indicates radiation field being measured has exceeded counting range of instrument
Audio Intensity can vary from approximately 68 dB to 100 dB through operation of the external rotary baffle and the internal voltage connection. Frequency is approximately 3 kHz
Remote Display Optional relay output available for connecting to remote displays (see remote display options)
Temperature Range -20 to 50 °C (-4 to 122 °F)
Power 9 Vdc wall-mount adapter handles any mains voltage in the world, supplied with four sets of prongs for almost any style wall receptacle
Battery Life 48 hours in non-alarm condition (typical)
12 hours in alarm condition (typical)
Battery Charger Battery is continuously trickle charged when instrument is connected to line power and turned on
Construction Aluminum housing with ivory powder coat
Size (H x W x L) 18.7 x 24.6 x 6.4 cm (7.4 x 9.7 x 2.5 in.)
Weight 2.1 kg (4.7 lb)

Graphs

CsI energy response

Options

OptionDescriptionPart Number
m375-options-web
Model 375 Series Options
Various options are available for the Model 375 Series including:
  • Enclosures
  • Remote displays
  • Alarm annunciators
  • Signal outputs
  • Software & networking options
Various

Documents

  • Data Sheet
  • Product Manual
  • Ethernet Manual Addendum (for instruments with ESP32 Ethernet board)
  • CE Certificate

Related Products

m375-face-for-slash2--slash4_d_500px_1525592625
Model 375/2
m375-face-for-slash2--slash4_d_500px_609338845
Model 375/4
m375-9_w_m45-9-g-trans_500px
Model 375-9
m375-10_500px
Model 375-10
Results 1 - 4 of 4

Ludlum Measurements, Inc.
501 Oak Street
Sweetwater, TX 79556
USA

(800) 622-0828 (US & Canada)
(325) 235-5494
(325) 235-4672

All Products

Service Center

Training

About Us

Careers

Ludlum Family

Directions to Facilities

U.S. Contacts

International Contacts

Privacy Policy

Follow Us

LinkedIn

Facebook

YouTube

© 2025 Ludlum Measurements, Inc.