Iodine Monitor UDI-201

For supplies to the Russian Federation


Procedure: Metrological certificate MVI №45540.8U136 dated 03.07.2008

continuous measurement of volumetric activity of I-131 radionuclide in both molecular and organic form

Main features and functions:

  • measurement of volumetric activity of I-131 radionuclide in air in both molecular and organic form; measurement data display (depending on version) and data output via RS485
  • work in spectrometer mode
  • automatic spectrum stabilization against temperature changes
  • automatic self-testing, alarm signal generation, alarm signal display and alarm output via RS485
  • two alarm threshold levels programming (warning and emergency levels)
  • alarm of measured value "minor change"
  • "dry-contact" signal of threshold value is exceeded
  • standard (0...20mA / 4...20mA) analog output for measured data transfer to external systems
  • standard (0...20mA / 4...20mA) analog input for external device connection and its measured data consideration in algorithms
  • pumped air monitoring and consumption measurement
  • unified and replaceable components for all "RADSYS" system devices

 Performance specification

Measurement range

lower limit: 3,7 Bq/m3, for measurements lasting 0÷15 min.
3,7×10-2 Bq/m3, for round-the-clock measurement
upper limit: 3,7×106 Bq/m3

Energy window

0,1 ÷ 3,00 MeV

Operating temperature range

0 to +55 °С

Operating pressure range

84,0 to 106,7 kPa 

Operating humidity range

up to 98 % at +35 °С

Relative error

not more than 50 %

Seismic stability

up to 8 points

Protection index


Dimensions and weight

DU: 380x300x390 mm; not more than 130 kg
LPDU: 390х200х190 mm; not more than 8 kg
LPU: 326х196х106 mm; not more than 4,5 kg
with frame: 784x725x420 mm; not more than 220 kg

Corresponds to 3N class requirements according to NP-001-97 (OPB-88/97)

Power supply

220 V

Power output

50 VA


Power supply 24 V
Display and buzzer
Two two-step or one-step relays
Mounted at a frame with terminal block
Aerosol filter