Page 5-16
Lasair II Particle Counter Operations Manual
Chapter 5: Setup
2
Tab to the Type field and select either Differential Counts or Total Counts.
NOTE:
The right tab key moves the cursor from the Alarm Enable
Button, to the Audible Alarm Button, to the Type Count Button, to the
Particle Alarms Table. Pressing the right tab key again will change the
display to the Analog Alarms Screen.
3
Tab to the Count field (N, N/ft.
3
, or N/M
3
).
NOTE:
N, N/M,
3
or N/ft.
3
is selected in the Sample Setup Screen.
4
Press Enter to activate the Count Field of your choice.
5
Use the arrow keys to move within the alarm table or to change alphanumeric
values.
6
Use the Enter key to initiate and confirm the change.
Pressing Enter also moves you into the Enable field, where the 1/0 field will be
highlighted.
7
Press Enter again to insert a “bullet” in the 1/0 radio button. The alarm setting is
now enabled.
Automatic Changes in Particle Alarms
Particle alarm settings will be automatically adjusted for changes made in the
sample settings so that the proportions will remain constant. For example:
•
If data is in the Raw mode, then changing the Time/Volume setting will also
change the alarms. If the Alarm is set to 10 particles and Time is set to 00:01:00,
and you change the time setting to 00:02:00, the alarm setting will automatically
be changed to 20 particles.
•
If data is changed from Raw to Normalized, the value of the new alarm will be
automatically changed to equal (Old Alarm/volume)
×
(1 ft.
3
/minute).
•
If data is changed from Normalized to Raw, the opposite happens. That is, New
Alarm = (Old Alarm
×
Volume)
×
(1 ft.
3
/minute).
•
If data is in Normalized mode and units change from ft.
3
to m
3
or from m
3
to ft.
3
,
the alarm is also automatically adjusted.
Setting Analog Alarms
To set an alarm for an analog parameter, you must have already enabled that
parameter in the Analog Data Setup Screen.
