Spectrometer facility for gamma-emitting radionuclide volumetric activity measurement in liquid SGM-01

Certificates:Certificate of measuring tool type approval №40243, valid till 01.04.2015 

automatic measurement of gamma-emitting radionuclide volumetric activity in coolant of NPP's first loop

Main features and functions:

  • medium sampling by means of sampling system valves in compliance with specified algorithm
  • instrument analysis of monitored medium gamma spectrum
  • calculation of discovered radionuclide activity and related values (minimum detectable activity, measurement error)
  • determination of measuring unit pollution level
  • measuring unit blow-down and rinsing
  • measurement quality control by means of monitored medium sampling (consumption) analysis and measurement equipment operability
  • calculated activity values comparison with set thresholds (warning and emergency thresholds)
  • visual and sound alarm of threshold exceeding
  • additional measuring unit rinse algorithm programming depending on measuring unit contamination level
  • automatic (cyclic) measurements, and measurements according to specified schedule
  • instrument spectrum storage (for the last month) and process results storage for the complete period of operation
  • immediate display of last measurement results
  • variation diagrams of monitored parameters for any period of operation
  • local computer network connection for remote spectrometer analysis monitor operation

 Performance specification

Operating temperature range

+5 to +50 °С

Operating pressure range

84 to 106,7 kPa

Operating humidity range

95 % at +30 °C

Protection index


Corresponds to 4 class requirements according to NP-001-97 (OPB-88/97)

Power supply

~220 V

Dimensions, weight

1355х536х450 mm; not more than 300 kg

Registered gamma radiation energy range   

50 ÷ 1500 keV

Volumetric activity measurement range        

8×104 ÷ 5×1010 Bq/m3

Limiting permissible main error (confidence probability 0,95)   

not more than 50 %

Sampling system


  • dimensions should be specified at design stage; system dimensions depend on number of monitoring points
  • electromagnetic contactor response time: not more than 1 second
  • electromagnetic contactor pressure: not more than 250 bar


Measurement chamber


  • volume: not more than 100 ml
  • measurement chamber structure allows running cleaning of measuring unit
  • lead screen thickness: not less than 0,1 m