Chapter 3: Configuring the 2085-IT8-SC/IT-16-SC Using CCW
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User’s Manual Pub. 0300322-01 Rev. A
table is invalid as the following,
•
The Process Alarm Low Value is equal to or greater than the Process
Alarm High Value.
•
The Process Alarm Low Value is less than the low limit of the selected
Input Type.
•
The Process Alarm High Value is greater than the high limit of the
selected Input Type.
Set the Process Alarm Low status bit in the Channel Status byte and the Channel
Fault bit when the channel input reading is equal to, or less than, the user-defined
Process Alarm Low Value entered in the configuration table.
Set the Process Alarm High status bit in the Channel Status byte and the Channel
Fault bit when the channel input reading is equal to, or greater than, the user-
defined Process Alarm High Value entered in the configuration table.
If Option 1 is selected,
The module will automatically clear the Process Alarm Low status bit in the
Channel Status byte and its Channel Fault bit when the channel input reading is
greater than the user-defined Process Alarm Low Value entered in the
configuration table.
The module will automatically clear the Process Alarm High status bit in the
Channel Status byte and its Channel Fault bit when the channel input reading is
less than the user-defined Process Alarm High Value entered in the configuration
table.
If Option 2 is selected,
The latch functions as follows:
Once the channel Process Alarm Low or High status bit is set as latched, it will
not be cleared even when the channel input reading is no longer:
•
Equal to, or less than, the user-defined Process Alarm Low Value.
OR
•
Equal to, or greater than, the user-defined Process Alarm High Value.
To clear the channel Process Alarm High or Low status bits when both of the
following conditions are satisfied:
•
The channel input reading is no longer:
-
Equal to, or less than, the user-defined Process Alarm Low Value.
OR
-
Equal to, or greater than, the user-defined Process Alarm High
Value.
•
The corresponding Clear Low or High Process Alarm Latch bit in the
output table has a value transition from 0 to 1.
Section 3.7 Under/Over Range Alarms
An Under Range or Over Range alarm is set if the channel input reading reaches,
or exceeds, the normal operating range. The alarm is not latched. If the reading
goes back into normal operating range, the alarm is automatically cleared. This
feature applies to all input types.
