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Configuration Sections

Alarm Logging Database

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Alarm Handling

Audit Trail

Database Configuration

Supported Databases

• SQLite (default, embedded)
• SQL Server
• PostgreSQL
• MySQL
• Oracle

Connection String Examples

SQLite (default):

Provider=System.Data.SQLite;Data Source=_ExecutionPathAndName_.dbAlarm

SQL Server:

Server=localhost;Database=AlarmHistory;Trusted_Connection=true;

PostgreSQL:

Host=localhost;Database=alarms;Username=user;Password=pass;

Startup Behavior

Initial Disable Time

Prevents nuisance alarms during startup:

• System initializes without triggering alarms
• Tags stabilize to normal values
• After timeout, normal alarm processing begins

Example: Set to 00:01:00 (1 minute) for complex systems

TimeDeadband Handling

When enabled:

• Alarms ignored during group deadband period
• Prevents alarm flooding
• Useful for known transient conditions

Shift-Based Limits

When Enable LimitsByShift is active:

• AlarmItems use Limit, Limit1, Limit2
• Different thresholds for different shifts
• Automatic switching based on schedule

See [Alarm Limits by Shift] for configuration

Audit Trail Configuration

Enabling Audit Trail

1. Check Enable Audit Trail
2. Select events to log
3. Configure database (uses alarm database)
4. View in AlarmViewer with List = "AuditTrail"

Custom Messages

Add via script:

csharp

@Alarm.GlobalSettings.AuditTrail.AddCustomMessage(
    message: "Batch completed",
    areaName: "Production",
    objectName: "Reactor1",
    value: "500",
    itemName: "BatchID",
    auxValue: "Grade A",
    comment: "Normal completion"
);

Runtime Control

csharp

// Enable/disable options at runtime
@Alarm.GlobalSettings.AuditTrail.UserLogonLogoff = true;
@Alarm.GlobalSettings.AuditTrail.TagChanges = false;

FDA 21 CFR Part 11 Compliance

For regulatory compliance:

1. Enable Audit Trail - Required
2. User Logon/Logoff - Track user access
3. Operator Actions - Record all changes
4. System Warnings - Log system events
5. Tag Changes - Track process modifications

Configure retention:

Life Time = 2555 days (7 years)

Runtime Access

Access settings programmatically:

csharp

// Check audit trail status
bool auditEnabled = @Alarm.GlobalSettings.AuditTrail.IsEnabled;

// Add custom message
@Alarm.GlobalSettings.AuditTrail.AddCustomMessage("Process started");

// Check database connection
string dbConnection = @Alarm.GlobalSettings.Database.Connection;

// Modify settings
@Alarm.GlobalSettings.LogUserFullName = true;

Best Practices

1. Size database appropriately - Audit trail generates significant data
2. Set reasonable retention - Balance compliance vs storage
3. Test startup delays - Find optimal disable time
4. Selective audit logging - Only log necessary events
5. Regular database maintenance - Archive old data
6. Document settings - For compliance audits
7. Monitor database growth - Prevent storage issues

Troubleshooting

Database connection failed:

• Verify connection string
• Check database service running
• Confirm network access
• Review user permissions

Audit trail not logging:

• Confirm Enable Audit Trail checked
• Verify specific options enabled
• Check database write permissions
• Review disk space

Alarms triggering at startup:

• Increase Initial Disable Time
• Enable Ignore During TimeDeadband
• Review startup sequence

Database growing too large:

• Set Life Time appropriately
• Archive old data regularly
• Consider separate audit database
• Optimize logged events

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