User`s manual

NexSens Technology, Inc.
iSIC User‟s Manual 73
The Define Alert/Alarm dialog box sets up a single alarm condition. To add multiple alarm
conditions, add them one at a time by click the Add button on the main alarm screen.
The Enable button enables the alarm. If you
would like to stop an alarm from occurring during
a period of time that you know a problem will
arise, simply uncheck the Enable box. All the
alarm information will still be saved.
The Category, either Alert or Alarm, specifies
what kind of text that is used when an alarm
occurs. Both alerts and alarm categories function
the same in iChart.
The alarm Type can either be: High threshold,
Low threshold, or Data Flag. Data flag alarms are
used to alarm on pre-defined data flag conditions.
These flags are setup in the Project | Setup
iChart Data Flag menu.
The Set Value is the value you want the alarm to trigger. For example click on Temperature C
on the left hand column and enter 50 for the Set Point. This means that if the temperature goes
above 50
o
C, an alarm will occur. This value can also be configured as a range instead of a set
point, such as only alarm when temperature falls between 50
o
C to 100
o
C. A range alarm, used
in conjunction with a set point alarm can allow you to send an alarm to an engineering technician
if the temperature is reading out of theoretical range (because of sensor failure or malfunction)
and send real alarms (caused by hot water) to a different person in charge of water
temperature.
The Reset Value is the value at which the alarm will allow it to trigger again. For example; if the
temperature went above 50
o
C an alarm would occur just once. If the Reset Point is set to 45
o
C,
then the alarm will not occur again until the temperature drops down below 45
o
C. This feature is
useful to prevent alarms from continuously occurring if temperature is jumping from 49.1
o
C to
50.1
o
C for example.
The Count is the number of times the condition has to occur before the alarm actions will occur.
The count is based on the data logger sample interval. For example, if the sample interval is 5
minutes and the count is 3, the alarm action would occur after 15 minutes of the alarm
condition. This feature is useful to prevent data spikes from causing alarm actions, such as
turbidity jumping to a large value due to a leaf floating by, etc.
After setting the alarm conditions, click on the „…‟ button located on the far right of the Alarm
Action field.