Watlow D4T Data Logger
•
65
•
Chapter 5 Function Reference
Logic
Set which state (on or off) of the alarm function's transmitter indicates there is an alarm.
Options:
• Close on Alarm:
the alarm function's transmitter is off when there is no alarm and on
when there is an alarm.
• Open on Alarm:
the alarm function's transmitter is on when there is no alarm and off
when there is an alarm.
Delay Time
Set a length of time, in seconds, that an alarm condition must be present before the alarm
state and output are triggered. This setting determines the minimum time that the value at IN
must be continuously above CTR by more than the high alarm set point or below CTR by more
than the low alarm set point before the alarm state and alarm function’s output indicate an
alarm. If the value at IN returns within the normal range before this time, no alarm occurs.
This feature can be used to minimize nuisance alarms.
Range: 0 to 9,999 seconds
Low Set Point
Set how far the value at IN must drop below CTR to trigger a low deviation alarm. The low
deviation alarm occurs when the value at IN is below the center’s value (CTR) plus this param-
eter’s setting. A negative value for Low Set Point sets the alarm condition below the center
and a positive value sets the alarm condition above the center.
Range: -99,999 to 99,999
High Set Point
Set how far the value at IN must rise above CTR to trigger a high deviation alarm. The high
deviation alarm occurs when the value at IN is above the center’s value (CTR) plus this param-
eter’s setting. A negative value for High Set Point sets the alarm condition below the center
and a positive value sets the alarm condition above the center.
Range: -99,999 to 99,999
Clear Alarm
Set this parameter to
clear
to reset the alarm state after correcting the condition that caused
the alarm.
Options: Ignore, Clear
Silence Alarm
Set this parameter to
silence alarms
to deactivate the output after the alarm occurs.
Options:
Ignore, Silence Alarms
Error Handling Rules
When the alarm's receiver (IN) has an error the alarm is triggered. The Alarm function never
generates an error and the output's error status is always None.
Error Condition
Result
Input has an error
The
Alarm State indicates there is an error and the output is active.