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Model 30-4

The Ludlum Model 30-4 joins the Model 30 digital display unit with a 22.9 cm (9 in.) REM ball containing a 3He detector, thereby providing a significant weight reduction and more compact, maneuverable instrument for determining neutron dose rates.Three modes of operation – RATE, MAX, and COUNT – are available for the user. Measurements can be collected in two sets of units (primary and secondary) for RATE and MAX modes in cps, cpm, rem/hr, or Sv/h units. An internal switch is used to enable or disable the front-panel setup feature to protect desired settings from inadvertent modification. Setup is also available via software from Ludlum Measurements.

This instrument features a large, easily-readable LCD (liquid crystal display) that may be rotated for maximum ease of use for the operator. The connecting cable is threaded through the rugged carrying handle to simplify use. In addition the display unit may be detached from REM ball permitting the operator to position the detector and the display unit to best advantage within the limits of the cable length. Other features are an audio warning tone and easy, intuitive, user-friendly design. Splash-resistant construction allows the Model 30 to be used in outdoor environments. The instrument body is constructed of lightweight, durable, high-impact plastic.

  • Multi-Function Digital Display Unit
  • Low-Weight Device Substitutes for Ratemeter
  • Simple Switching Between Two Sets of Measurement Units
  • Moderated Neutron Detector
  • Range: 0 to 99.9 mSv/h (0 to 9.99 rem/hr)
  • Display Unit Detaches for Greater Versatility
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