Alarms Configuration for OPC
To configure workstation alarms for a point, the following fields are available in a CSV configuration file:
- Alarm Class
- Alarm Type
- Alarm Value
- Event Text
- Normal Text
- Upper Hysteresis
- Lower Hysteresis
For a detailed description of these fields, see OPC Items Data.
After you import an OPC configuration file, you can configure workstation alarms for individual OPC points from the Alarm Configuration expander in the Object Configurator tab (see Alarm Configuration).
Supported Alarm Type Operators
Alarm Type Operator | Operand | Meaning | Applicable Alarm Category |
EQ | = | equal to | Discrete |
NE | != | not equal to | Discrete |
LT | < | less then | Continuous |
LE | <= | less than or equal to | Continuous |
GT | > | greater than | Continuous |
GE | >= | greater than or equal to | Continuous |
BET | .. | between | Discrete |
NBET | !.. | not between | Discrete |
Note that:
- EQ is the only supported alarm type value for binary (Boolean) points.
- Only one alarm can be specified for binary (Boolean) points.
- Alarm configuration is ignored in the following cases:
- Discrete and continuous alarms are mixed.
- The number of alarm values/range is inconsistent in the alarm configuration columns.
- BET and NBET are not supported for items with state texts.
Examples of Alarm Configuration
After the import of a CSV file:
- An individual alarm is configured as follows:
Alarm Configuration in the CSV File | Configuration imported into the Alarm Configuration expander |
[Alarm Class]; Alarm | Alarm Class: Alarm |
[Alarm Type]: EQ [Alarm Value]: 1 | Value Range: = (1) |
[Event Text]: Binary Input | Event Text: Boolean Alarm |
[Normal Text]: Normal | Normal Text: Normal |
- Multiple alarms are configured as follows:
Alarms Configuration in the CSV File | Configuration imported in the Alarm Configuration expander |
[Alarm Class]; Alarm$Fault | Alarm Class: Alarm, Fault |
[Alarm Type]: EQ$BET [Alarm Value]: 10$[12$15] | Alarm Value Range: = 10 Fault Value Range: = 12 to 15 |
[Event Text]: Analog Alarm$Fault Alarm | Alarm Event Text: Analog Alarm Fault Event Text: Fault Alarm |
[Normal Text]: No Alarm$No Fault | Alarm Normal Text: No Alarm Alarm Normal Text: No Fault |