Under/Over Range Alarms - Spectrum Controls Micro800 2085-IR8-SC User Manual

Chapter 3: Configuring the Micro800 Expansion I/O 2085-IR8-SC Using CCW
The firmware sets 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.
The firmware sets 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 automatically clears 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 automatically clears 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, latching operates as follows:
•
Once the channel Process Alarm Low or High status bit is set as latched,
it is not be cleared even when the channel input reading is no longer:
•
To clear the channel Process Alarm High or Low status bits when both of
the following conditions are satisfied:

3.6.10 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.
The Under Range and Over Range status bits are defined in the Channel Bit and
value allocation of the Input Table.
•
When the channel input reading is equal to, or less than, the minimum
point of the selected Input Type range, the Channel Under Range status
bit and the Channel Fault bit are set. If the channel input reading reaches
-
The Process Alarm High Value is greater than the high limit of
the selected Input Type.
-
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 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.
User's Manual Pub. 0300321-01 Rev. A
3-27