Fluke Biomedical 451P - Manual (Page 16)

451P
Operators Manual
6
Specifications
Radiation Detected ............................................... Beta above 1 MeV & gamma above 25 KeV
Operating Ranges ................................................. 0
μ R/hr to 500 μ R/hr (0 μ Sv/h to 5 μ Sv/h), 0 mR/h to 5 mR/h (0 μ Sv/h
to 50 μ Sv/h) 0 mR/h to 50 mR/h (0 μ Sv/h to 500 μ Sv/h), 0 mR/h to
500 mR/h (0 mSv/h to 5 mSv/h), 0 R/h to 5 R/h (0 mSv/h to 50 mSv/h)
Accuracy ................................................................ ± 10 % of reading between 10 % and 100 % of full-scale indication on
any range, exclusive of energy response (calibration source is 137 Cs)
Detector ................................................................. 230 cc active volume air ionization chamber, pressurized to
8 atmospheres. Plastic chamber wall 200 mg/cm2 thick
Warm-Up Time ....................................................... Less than one minute for initial operation when the instrument is in
temperature equilibrium with the surrounding area and about 4 minutes
for readings less than 20
μ R/h in a 10 μ R/h or less background.
Drift ......................................................................... After seven minutes operation, 0.04 mR/h equivalent, or less
Response Time ..................................................... Time measured from 10 % to 90 % of final value for a step
increase/decrease in radiation rate such that a range change does not
occur:
0 μ R/h to 500 μ R/h (0 μ Sv/h to 5 μ Sv/h) range: 5 seconds. 0 mR/hr to
5 mR/hr (0 μ Sv/h to 50 μ Sv/h) range: 2 seconds. 0 mR/h to 50 mR/h
(0 μ Sv/h to 500 μ Sv/h) range: 1.8 seconds. 0 mR/h to 500 mR/h
(0 mSv/h to 5 mSv/h) range: 1.8 seconds. 0 R/h to 5 R/h (0 mSv/h to
50 mSv/h) range: 1.8 seconds.
NOTE: In pulsating field, the instantaneous rate should not exceed
5 R/h for proper integration; instantaneous exposure rate is still limited
to 5 R/h
Precision ................................................................ Within 5 % reading
Readout .................................................................. Liquid Crystal Display: contains an analog bar graph with a permanent
scale on the display and a 2½ digit display. Analog Display: the bar
graph consists of 100 segments, 2½ inches long; the scale has five
major divisions; the appropriate value for the operating range of the
instrument will appear below the scale. Digital Display: the digital
display is 2½ digits followed by a significant zero digit depending on
the operating range of the instrument. The leading ½ digit is blank, or a
“1” or a “0” for clarity. Units of measure appear to the right of the digital
display. Appropriate multipliers also appear on the display
Units: as indicated under Range, programmable in R/h or Sv/h.
Appropriate multipliers also appear on the display. Auto-On Backlight:
turns on when ambient light is less then twilight conditions.
External Controls .................................................. ON/OFF button, MODE button
Automatic Features .............................................. Ranging and zeroing are fully automatic.