LUDLUM MODEL 2241-2 Technical Manual page 11

Model 2241-2
Ludlum Measurements, Inc.
Technical Manual
calibration or at the time the instrument is received in the field.
If at any time the instrument fails to read within 20% of the reference
reading when using the same check source, it should be sent to a calibration
facility for recalibration and/or repair. If desired, multiple readings may be
taken at different distances and/or with different sources so that other
ranges or scales are checked.
Switch the
AUD ON
unimorph speaker produces an audible click for each event detected (audio
divide-by 1 parameter). The
the position; however, an audible alarm condition will still be heard.
OFF
Increase the source activity or lower the alert and alarm points to initiate an
and
ALERT ALARM
Switchboard Parameters.") Depress the
audible alarm. Decrease the radiation activity below the
threshold, and depress the
alarm condition is not present, depressing the
reset the alert condition and zero the ratemeter.
Position a check source to produce a ratemeter reading of 100 to 2000
counts/minute or 10-100 µR/hr. While observing the ratemeter fluctuations,
select between the fast and slow response time (
variations in the display. The
times slower than the
slower when in variable response mode. The slow response position is
normally used when the Model 2241-2 is displaying low numbers, which
require a more stable display. The fast response position is used at high
count levels.
Move the /
OFF SCALER
the switch located in the end of the carrying handle in order to
COUNT
initiate a count cycle. The word "
LCD during the count cycle and should disappear at the end of the
predetermined count time. If a scaler
switch can be depressed to acknowledge the alarm; however, the
switch must be depressed to clear the visual
cycle.
Depress and release the
LCD should illuminate (for pre-programmed
/ , /
F S AUD ON OFF
use the instrument.
/ switch to the
OFF ON
/
AUD ON OFF
condition. (Refer to Section 8, "Entering or Changing
switch to clear the alarm conditions. If an
RESET
position should respond approximately five
S
position (for fixed response mode) and three times
F
/ switch to the
RATEMETER
COUNTING
ALARM
switch. The backlight located behind the
LIGHT
, and or
RATEMETER SCALER
Page 2-3
position and confirm the external
switch will silence the clicks if in
switch to acknowledge the
RESET
ALERT
switch the first time will
RESET
/ ) positions to observe
F S
position. Depress
SCALER
" should be flashing on the
condition occurs, the
and to restart the count
ALARM
time). Select the desired
ON
parameters and proceed to
January 2016
Section 2
and
ALARM
RESET
COUNT