ViewSmart 200/2050/2150 Controller User's Manual
Document: UM-1021
Revision Level B
10
Figure 2.3
2.2.3
ALARM 1 / ALARM 2 / ALARM 3 SET-UP MENUs
Alarms 1, 2 and 3 have identical menus. The only difference between each is A1 front
panel LED indicators are yellow while A2’s and A3’s are red. Typical applications often
have A1 set at a WARN level, A2 at a HIGH level and A3 at a negative FAULT level.
However, it is important to understand there is no functional difference between A1, A2
and A3. Since their configuration menus are identical, only one is shown in Figure 2.3.
Figure 2.4
Set Point
is entered in engineering units and determines the value where the alarm
trips. For example, if a channel monitors 0-50 ppmH2S and the desired alarm level is
10 ppm, the correct entry is 10.00. A one percent dead band prevents alarm chatter.
This means after tripping an alarm the input must move at least 1% of full scale back
through the setpoint for the alarm to auto reset.
The
ON Delay / OFF Delay
entries allow
ON
and
OFF
time delays affecting how
long the trip-point must be surpassed before an alarm event transition occurs.
ON
delays are limited to 10 seconds while
OFF
delays may be as long as 120 minutes.
Delays are useful in many applications to prevent nuisance alarms and unwanted
cycling into and out of alarm conditions.
