LUDLUM 26-1 User Manual

Model 26-1 Frisker User’s Manual Section 5
Ludlum Measurements, Inc. Page 5-5 April 2017
Efficiency (Default 15.0%) - Use ON/ACK to select the value to adjust, and
MODE to adjust the value. Available values are:
Ones Place (0-9)
Tens Place (0-9)
Hundreds Place (0-9)
Number of Decimal Places (0 or 1)
Normally the efficiency is used on a per detector basis, i.e. the efficiency of the
detector is calculated by dividing the count rate received from a source by the
total disintegration rate of the source. But if the user desires to have the Model
26-1 show results in terms of dpm/100 cm
2
, the user could manipulate the
efficiency to produce this result : efficiency = count rate/disintegration rate/6.7.
The factor of 6.7 is the ratio of 100 cm
2
to 15 cm
2
, which is the size of the
pancake detector. If we start with the default value of 15% to measure in dpm,
then the parameter could be changed to 2.2% to measure in dpm/100 cm
2
.
Or likewise for Bq/cm
2
, efficiency could be calculated as: efficiency =
countrate/disintegration rate*15. Again, the factor of 15 is because the area of
the pancake detector is 15 cm
2
. If we start with the default value of 15% to
measure in Bq, then the parameter could be changed to 225% to measure in
Bq/cm
2
.
Primary Units (Default cpm) - Use MODE to select. Available values are cps,
cpm, Bq, dpm, mR/h, and µSv/h.
Primary Units RATE/MAX Mode Alarm Point (Default 000) - Use
ON/ACK to select the value to adjust, and MODE to adjust the value. Units
will be the same as selected earlier with Primary Units. The ALARM LCD
Segment will be on to indicate an Alarm parameter. Set this Alarm Point to 000
to disable. Available values are:
Ones Place (0-9)
Tens Place (0-9)
Hundreds Place (0-9)
Thousands Place (1 on or off)
Number of Decimal Places (0, 1, or 2– only available if k selected)
Range (k on or off – not available for mR/h or µSv/h)
Note: If the Primary Units has changed to a value other than that used to
previously set this Alarm Point, the Alarm Point will be reset to 000.

LUDLUM 26-1 Specifications

General

Brand	LUDLUM
Model	26-1
Category	Measuring Instruments
Language	English