Intrinsically Safe Ratemeter - Model 3-IS
CE Seal

This intrinsically safe general purpose ratemeter is patterned after Ludlum's best-selling Model 3. It was designed and tested to USA standards for intrinsic safety, permitting it to be used in potentially explosive atmospheres. The Model 3-IS can only be used with select detectors to sustain the intrinsic safety rating. The optional detectors for this application are:
  • Model 44-9:     15 cm² GM pancake probe
  • Model 44-2:     2.5 x 2.5 cm (1 x 1 in.) NaI scintillator
  • Model 44-6:     GM gamma probe with beta window
  • Model 44-7:     6 cm² active window GM for alpha, beta, gamma
  • Model 44-38:   energy compensated GM probe with beta window
  • Model 42-41L: proton recoil type neutron detector
Like the Model 3 before it, the 3-IS retains the well-deserved reputation for accuracy and long-lasting dependability. The aluminum cast instrument housing, with its separate battery compartment and accompanying metal handle, offer an industrial robustness and quality that promote long-lasting protection and instrument life. The front-panel controls include a rotary switch for selecting the four-decade range, instrument shut-off, and battery test, an audio on/off switch, a fast/slow response switch, and a count reset button. The analog meter comes in a variety of measurement ranges and units to support the external radiation detector selected.
A one meter (39 in.) straight type detector cable equipped with special connectors designed to prevent quick or accidental disconnection in the field is included in the price of the instrument.