LX Series Unit Ventilator Controller User's Guide
61
Alarm Features
UVC alarms have a number of features that enable you to automatically and
carefully monitor critical system information. Many of these features are visible in
Figure 27. Table 9 describes alarm features.
Table 9: Alarm Features (Part 1 of 2)
Feature
Description
Monitored Variable
Displays the network variable or control point that is monitored by the
alarm. For example, if you have an alarm that sends a message
whenever a space temperature deviates too far from the setpoint, then
the monitored variable is the space temperature.
Alarm State
Enables when a monitored variable has a value that causes an alarm.
Alarm Offset
Displays the amount that the monitored variable can deviate from the
setpoint before entering the alarm state. See Figure 27. An offset
causes the alarm to become active when the value of the monitored
variable is greater than or less than the range of values equal to the
setpoint plus or minus the offset. Alarms that use an alarm offset are
often called deviation alarms.
Alarm Delay
Displays the period of time that the monitored variable must be in the
alarm state before an alarm message is generated. See Figure 27 and
Figure 28.
Spa
c
e Temp
C°
Features of a Deviation Alarm
Setpoint
22
20
15
25
2.
0 C°
2.
0 C°
Monitored
Variable
Upper
limit of
Offset
Lower
limit of
Offset
Monitored variable exceeds value of setpoint
at this time.
An alarm message is not sent as the monitored
variable is in the alarm state for less time than the
value of the alarm delay.
Monitored variable
enters alarm state
at this time.
Alarm message is
sent here after the
expiration of the
alarm delay.
Time
Offset = 2C°
Alarm Delay = 10 minutes
10.0 min
10.0 min
Figure 27: Space Temperature Alarm