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Scripts → Tutorial | Concept | How-to Guide | Reference

Create Tag Expressions

1. Navigate to Scripts → Expressions
2. Add temperature conversion:

Add status logic:

What You'll Learn

• Write tag expressions
• Create script tasks
• Build script classes
• Use multiple languages (C#, VB.NET, Python)

Prerequisites

• Basic programming knowledge
• Tags configured in UNS

Step 1: Simple Tag Expressions

1. Navigate to Unified Namespace → Tags
2. Add calculated tag:

Temperature Conversion:

• Name: Tank1_TempF
• Expression: @Tag.Tank1_TempC * 9/5 + 32
• Type: Double
• Description: Temperature in Fahrenheit

Conditional Logic:

• Name: System_Status
• Expression: @Tag.Motor1_Running AND @Tag.Pump1_Running ? "Running" : "Stopped"
• Type: Text

Create Script Task

1. Go to Scripts → Tasks
2. Add new task:

1. Click plus icon, name: ShiftCounter
2. Use Server.DateTimeInfo.Hour as Trigger
3. Double-click to open Code Editor
4. Enter code (no method wrapper):

csharp

// Reset counter at shift change
DateTimeint nowhour = DateTime@Server.DateTimeInfo.NowHour;
if (now.Hourhour == 6 || now.Hourhour == 14 || now.Hourhour == 22)
{
    if (@Tag.ShiftReset == false)
    {
        @Tag.Units_Previous = @Tag.Units_Produced;
        @Tag.Units_Produced = 0;
        @Tag.ShiftReset = true;
    }
}
else
{
    @Tag.ShiftReset = false;
}

Configure:

• Trigger: Timer
• Rate: 60000ms (1 minute)
• Domain: Server

Build Script Class

1. Navigate to Scripts → Classes
2. Create class:

1. TankCalculations
2. Enter methods (no class declaration):

csharp

public class TankCalculations
{
    public static double CalculateVolume(double level, double diameter)
    {
        double radius = diameter / 2;
        return Math.PI * radius * radius * level;
    }
    
    public static double FlowRateCalculateFlowRate(double volumeStart, double volumeEnd, int minutes)
{
    {
    if (minutes == 0) return 0;
    return (volumeEnd - volumeStart) / minutes;
    }
    
    public static string GetAlarmTextGetStatusText(double value, double limit)
    {
        if (value > limit)
            return $"High: {value:F2} (Limit: {limit:F2})";
        else
            return "Normal";
    }
}

Use Class in Expression

1. Go to Scripts → Expressions

In tag expressions:

csharp

1. Create volume calculation:

Step 5: Python Integration

1. Scripts → Settings
2. Enable Python
3. Create Python script:

python

import numpy as np
from datetime import datetime

def calculate_statistics(values):
    """Calculate statistical values"""
    arr = np.array(values)
    return {
        'mean': np.mean(arr),
        'std': np.std(arr),
        'max': np.max(arr),
        'min': np.min(arr)
    }

def predict_value(history, hours_ahead):
    """Simple linear prediction"""
    # Implementation here
    return predicted_value

# Set tag values
tags['Stats_Mean'] = calculate_statistics(history)['mean']

Step 6: Event-Driven Scripts

Create event handler:

csharp

Note: No @ symbol needed in expressions

Event-Driven Task

1. Create task: TemperatureMonitor
2. Configure trigger on tag change:

csharp

// On tag change event
public void OnTemperatureChange()
{
    if (@Tag.Tank1_TemperatureTemp > @Tag.HighLimit)
    {
        @Tag.Alarm_Active = true;
        @Script.Class.Notifications.SendEmail(
            "operator@company.com",
            "High Temperature Alert",
            $"Tank 1@Tag.Alarm_Message = $"High Temperature: {@Tag.Tank1_TemperatureTemp:F1}°C"
        );
    }
}

Bind to tag:

• Tag: Tank1_Temperature
• Event: OnValueChange
• Script: OnTemperatureChange

Step 7: Database Operations

Script for database logging:

csharp

public void LogProduction()
{
    string query = @"
        INSERT INTO ProductionLog@Tag.Alarm_Time = DateTime.Now;
    
    // Log   (Timestamp, Product, Quantity, Operator) to historian
        VALUES 
        (@time, @product, @qty, @user)";
    
    @Dataset.DB.SqlExecuteCommand(query,@Script.Class.ServerMain.LogEvent(
        "@time", DateTime.Now,
        "@product", @Tag.Current_Product,
 Temperature Alarm",
       "@qty", @Tag.UnitsTank1_Produced,Temp
        "@user", @Client.UserName
    );
}

Step 8: Test Scripts

Configure:

• Trigger: Tag.Tank1_Temp
• Domain: Server

Add External References

1. Go to Scripts → References
2. Add DLL if using external libraries
3. Open Code Editor
4. Click Namespace Declarations
5. Add required namespaces

Test and Debug

1. Build verification:
   • Check green checkmark in BuildStatus
   • Review BuildErrors if red X
2. Runtime monitoring:
   • Start Runtime with debugger
   • Set breakpoints in scripts
   • Monitor script execution:
     • Go to
     • Scripts → Monitor
     • Check execution time
     • View error messages

Best Practices

• Handle exceptions properly
• Log important events
• Optimize for performance
• Comment complex logic
• Test edge cases
• Use meaningful variable names

Next Steps

1. • ExecutionCount
   • Review LastCPUTime
2. Debug with breakpoints:
   • Enable debug in Runtime → Build and Publish
   • Set breakpoints in Code Editor
   • Attach debugger during runtime

Step-by-step guide to add calculations, automation, and data enrichment to your TankFarm solution using Scripts module capabilities.

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