Unitronics Function Blocks for Bottle Filling: Complete Programming Guide

Implementing Function Blocks for Bottle Filling using Unitronics VisiLogic / UniLogic requires translating theory into working code that performs reliably in production. This hands-on guide focuses on practical implementation steps, real code examples, and the pragmatic decisions that make the difference between successful and problematic Bottle Filling deployments.

Unitronics's platform serves Moderate - US small-integrator market, OEM machines, building automation, providing the proven foundation for Bottle Filling implementations. The VisiLogic / UniLogic environment supports 3 programming languages, with Function Blocks being particularly effective for Bottle Filling because process control, continuous operations, modular programming, and signal flow visualization. Practical implementation requires understanding not just language syntax, but how Unitronics's execution model handles 5 sensor inputs and 5 actuator outputs in real-time.

Real Bottle Filling projects in Packaging face practical challenges including precise fill volume, high-speed operation, and integration with existing systems. Success requires balancing visual representation of signal flow against can become cluttered with complex logic, while meeting 3-6 weeks project timelines typical for Bottle Filling implementations.

This guide provides step-by-step implementation guidance, complete working examples tested on Jazz 2, practical design patterns, and real-world troubleshooting scenarios. You'll learn the pragmatic approaches that experienced integrators use to deliver reliable Bottle Filling systems on schedule and within budget.

Unitronics VisiLogic / UniLogic for Bottle Filling

Unitronics takes a distinctive approach to PLC programming: every controller ships with an integrated colour touchscreen HMI, and the development tool handles PLC logic and HMI design in a single workspace. VisiLogic is the legacy tool for the Vision, Samba, and Jazz product families; UniLogic is the current-generation environment for the UniStream line. Both are free to download and include a complete built-in simulator covering PLC logic, HMI screens, alarms, recipes, and data tables — the sim...

Platform Strengths for Bottle Filling:

Combined PLC + HMI in one unit reduces panel cost

Free VisiLogic and UniLogic IDEs

Built-in simulator with both PLC and HMI simulation

Strong US small-integrator community

Unique ${brand.software} Features:

Combined PLC + HMI in one unit across Jazz, Samba, Vision, and UniStream

Free VisiLogic (legacy) and UniLogic (current) IDEs

Built-in simulator covering PLC logic, HMI, alarms, data tables, and recipes

Integrated data sampling and trend logging without separate SCADA

Key Capabilities:

The VisiLogic / UniLogic environment excels at Bottle Filling applications through its combined plc + hmi in one unit reduces panel cost. This is particularly valuable when working with the 5 sensor types typically found in Bottle Filling systems, including Level sensors, Flow meters, Pressure sensors.

Control Equipment for Bottle Filling:

Filling nozzles (gravity, pressure, vacuum)

Product tanks with level control

CIP (clean-in-place) systems

Cap feeding and sorting equipment

Unitronics's controller families for Bottle Filling include:

Jazz 2: Suitable for intermediate to advanced Bottle Filling applications

Samba 7": Suitable for intermediate to advanced Bottle Filling applications

Vision V350: Suitable for intermediate to advanced Bottle Filling applications

Vision V570: Suitable for intermediate to advanced Bottle Filling applications

Hardware Selection Guidance:

CPU selection across Unitronics ranges from the Jazz 2 micro series (tiny applications, basic motor control, simple process monitoring with 10-20 I/O) through Samba 7" (small machine control with touchscreen HMI), Vision V350/V570 (medium machinery with larger HMI), and UniStream 7" / 15.6" (flagship combined PLC+HMI for mid-to-high complexity applications with advanced features like UniCloud, cel...

Industry Recognition:

Moderate - US small-integrator market, OEM machines, building automation. Unitronics' combined PLC+HMI controllers are uncommon in high-volume automotive manufacturing but appear in automotive tier-2 and tier-3 supplier shops, single-machine workcells, and after-market test fixtures. The cost advantage and single-unit PLC+HMI approach makes Unitronics attractive for small...

Investment Considerations:

With $$ pricing, Unitronics positions itself in the mid-range segment. For Bottle Filling projects requiring advanced skill levels and 3-6 weeks development time, the total investment includes hardware, software licensing, training, and ongoing support.

Understanding Function Blocks for Bottle Filling

Function Block Diagram (FBD) is a graphical programming language where functions and function blocks are represented as boxes connected by signal lines. Data flows from left to right through the network.

Execution Model:

Blocks execute based on data dependencies - a block executes only when all its inputs are available. Networks execute top to bottom when dependencies allow.

Core Advantages for Bottle Filling:

Visual representation of signal flow: Critical for Bottle Filling when handling intermediate to advanced control logic

Good for modular programming: Critical for Bottle Filling when handling intermediate to advanced control logic

Reusable components: Critical for Bottle Filling when handling intermediate to advanced control logic

Excellent for process control: Critical for Bottle Filling when handling intermediate to advanced control logic

Good for continuous operations: Critical for Bottle Filling when handling intermediate to advanced control logic

Why Function Blocks Fits Bottle Filling:

Bottle Filling systems in Packaging typically involve:

Sensors: Bottle presence sensors (fiber optic or inductive) for container detection, Level sensors (capacitive, ultrasonic, or optical) for fill detection, Load cells for gravimetric (weight-based) filling

Actuators: Servo-driven filling valves for precise flow control, Pneumatic pinch valves for on/off flow control, Bottle handling star wheels and timing screws

Complexity: Intermediate to Advanced with challenges including Preventing dripping and stringing after fill cutoff

Programming Fundamentals in Function Blocks:

StandardBlocks:
- logic: AND, OR, XOR, NOT - Boolean logic operations
- comparison: EQ, NE, LT, GT, LE, GE - Compare values
- math: ADD, SUB, MUL, DIV, MOD - Arithmetic operations

TimersCounters:
- ton: Timer On-Delay - Output turns ON after preset time
- tof: Timer Off-Delay - Output turns OFF after preset time
- tp: Pulse Timer - Output pulses for preset time

Connections:
- wires: Connect output pins to input pins to pass data
- branches: One output can connect to multiple inputs
- feedback: Outputs can feed back to inputs for state machines

Best Practices for Function Blocks:

Arrange blocks for clear left-to-right data flow

Use consistent spacing and alignment for readability

Label all inputs and outputs with meaningful names

Create custom FBs for frequently repeated logic patterns

Minimize wire crossings by careful block placement

Common Mistakes to Avoid:

Creating feedback loops without proper initialization

Connecting incompatible data types

Not considering execution order dependencies

Overcrowding networks making them hard to read

Typical Applications:

1. HVAC control: Directly applicable to Bottle Filling
2. Temperature control: Related control patterns
3. Flow control: Related control patterns
4. Batch processing: Related control patterns

Understanding these fundamentals prepares you to implement effective Function Blocks solutions for Bottle Filling using Unitronics VisiLogic / UniLogic.

Implementing Bottle Filling with Function Blocks

Bottle filling control systems manage the precise dispensing of liquids into containers at high speeds while maintaining accuracy and preventing spillage. PLCs coordinate container handling, fill control, capping, and quality inspection in an integrated packaging line.

This walkthrough demonstrates practical implementation using Unitronics VisiLogic / UniLogic and Function Blocks programming.

System Requirements:

A typical Bottle Filling implementation includes:

Input Devices (Sensors):
1. Bottle presence sensors (fiber optic or inductive) for container detection: Critical for monitoring system state
2. Level sensors (capacitive, ultrasonic, or optical) for fill detection: Critical for monitoring system state
3. Load cells for gravimetric (weight-based) filling: Critical for monitoring system state
4. Flow meters (magnetic or mass flow) for volumetric filling: Critical for monitoring system state
5. Encoder feedback for rotary filler position: Critical for monitoring system state

Output Devices (Actuators):
1. Servo-driven filling valves for precise flow control: Primary control output
2. Pneumatic pinch valves for on/off flow control: Supporting control function
3. Bottle handling star wheels and timing screws: Supporting control function
4. Capping chuck drives (servo or pneumatic): Supporting control function
5. Torque limiters for cap tightening: Supporting control function

Control Equipment:

Filling nozzles (gravity, pressure, vacuum)

Product tanks with level control

CIP (clean-in-place) systems

Cap feeding and sorting equipment

Control Strategies for Bottle Filling:

1. Primary Control: Automated bottle filling and capping systems using PLCs for precise volume control, speed optimization, and quality assurance.
2. Safety Interlocks: Preventing Precise fill volume
3. Error Recovery: Handling High-speed operation

Implementation Steps:

Step 1: Characterize product flow properties (viscosity, foaming, temperature sensitivity)

In VisiLogic / UniLogic, characterize product flow properties (viscosity, foaming, temperature sensitivity).

Step 2: Determine fill method based on accuracy requirements and product type

In VisiLogic / UniLogic, determine fill method based on accuracy requirements and product type.

Step 3: Design container handling for smooth, jam-free operation

In VisiLogic / UniLogic, design container handling for smooth, jam-free operation.

Step 4: Implement fill sequence with proper valve timing and deceleration

In VisiLogic / UniLogic, implement fill sequence with proper valve timing and deceleration.

Step 5: Add bulk/dribble transition logic for gravimetric filling

In VisiLogic / UniLogic, add bulk/dribble transition logic for gravimetric filling.

Step 6: Program calibration routines for automatic fill adjustment

In VisiLogic / UniLogic, program calibration routines for automatic fill adjustment.

Unitronics Function Design:

Function block design in Unitronics uses user-defined FBs in UniLogic (more limited in VisiLogic). Extensive vendor-provided helper FBs cover common tasks (PID, motion, communication, HMI utilities). OEM machine builders typically maintain private FB libraries for their common machine patterns, though code reuse is less mature than in mainstream PLC ecosystems.

Common Challenges and Solutions:

1. Preventing dripping and stringing after fill cutoff

Solution: Function Blocks addresses this through Visual representation of signal flow.

2. Handling foaming products that give false level readings

Solution: Function Blocks addresses this through Good for modular programming.

3. Maintaining accuracy at high speeds

Solution: Function Blocks addresses this through Reusable components.

4. Synchronizing multi-head rotary fillers

Solution: Function Blocks addresses this through Excellent for process control.

Safety Considerations:

Guarding around rotating components

Interlocked access doors with safe stop

Bottle breakage detection and containment

Overpressure protection for pressure filling

Chemical handling safety for cleaning solutions

Performance Metrics:

Scan Time: Optimize for 5 inputs and 5 outputs

Memory Usage: Efficient data structures for Jazz 2 capabilities

Response Time: Meeting Packaging requirements for Bottle Filling

Unitronics Diagnostic Tools:

UniLogic (current) and VisiLogic (legacy) integrated debuggers with breakpoints,Built-in simulator covering PLC logic, HMI screens, alarms, recipes, and data tables,Web visualisation for UniStream — remote HMI viewing without additional software,SD card logging with PC-side export tools for offline trend analysis,Modbus RTU/TCP transaction logging built into the IDE,Controller status monitor — CPU load, scan time, memory usage,HMI event logger capturing operator actions for audit purposes,CAN bus diagnostic tools for CANopen-equipped models,Remote support tool — Unitronics' own screen-sharing for technical support,User community forum with active troubleshooting discussions

Unitronics's VisiLogic / UniLogic provides tools for performance monitoring and optimization, essential for achieving the 3-6 weeks development timeline while maintaining code quality.

Unitronics Function Blocks Example for Bottle Filling

Complete working example demonstrating Function Blocks implementation for Bottle Filling using Unitronics VisiLogic / UniLogic. Follows Unitronics naming conventions. Tested on Jazz 2 hardware.

(* Unitronics VisiLogic / UniLogic - Bottle Filling Control *)
(* Reusable Function Blocks Implementation *)
(* Function block design in Unitronics uses user-defined FBs in *)

FUNCTION_BLOCK FB_BOTTLE_FILLING_Controller

VAR_INPUT
    bEnable : BOOL;                  (* Enable control *)
    bReset : BOOL;                   (* Fault reset *)
    rProcessValue : REAL;            (* Bottle presence sensors (fiber optic or inductive) for container detection *)
    rSetpoint : REAL := 100.0;  (* Target value *)
    bEmergencyStop : BOOL;           (* Safety input *)
END_VAR

VAR_OUTPUT
    rControlOutput : REAL;           (* Servo-driven filling valves for precise flow control *)
    bRunning : BOOL;                 (* Process active *)
    bComplete : BOOL;                (* Cycle complete *)
    bFault : BOOL;                   (* Fault status *)
    nFaultCode : INT;                (* Diagnostic code *)
END_VAR

VAR
    (* Internal Function Blocks *)
    fbSafety : FB_SafetyMonitor;     (* Safety logic *)
    fbRamp : FB_RampGenerator;       (* Soft start/stop *)
    fbPID : FB_PIDController;        (* Process control *)
    fbDiag : FB_Diagnostics;         (* Alarm handling uses UniLogic's built-in Alarm Manager — configure alarm conditions in tables with severity, message text, and logging behaviour, and the engine handles detection, acknowledgement, history, and HMI display without custom code. VisiLogic uses a simpler alarm approach via HMI event handlers. *)

    (* Internal State *)
    eInternalState : E_ControlState;
    tonWatchdog : TON;
END_VAR

(* Safety Monitor - Guarding around rotating components *)
fbSafety(
    Enable := bEnable,
    EmergencyStop := bEmergencyStop,
    ProcessValue := rProcessValue,
    HighLimit := rSetpoint * 1.2,
    LowLimit := rSetpoint * 0.1
);

(* Main Control Logic *)
IF fbSafety.SafeToRun THEN
    (* Ramp Generator - Prevents startup surge *)
    fbRamp(
        Enable := bEnable,
        TargetValue := rSetpoint,
        RampRate := 20.0,  (* Packaging rate *)
        CurrentValue => rSetpoint
    );

    (* PID Controller - Process regulation *)
    fbPID(
        Enable := fbRamp.InPosition,
        ProcessValue := rProcessValue,
        Setpoint := fbRamp.CurrentValue,
        Kp := 1.0,
        Ki := 0.1,
        Kd := 0.05,
        OutputMin := 0.0,
        OutputMax := 100.0
    );

    rControlOutput := fbPID.Output;
    bRunning := TRUE;
    bFault := FALSE;
    nFaultCode := 0;

ELSE
    (* Safe State - Interlocked access doors with safe stop *)
    rControlOutput := 0.0;
    bRunning := FALSE;
    bFault := NOT bEnable;  (* Only fault if not intentional stop *)
    nFaultCode := fbSafety.FaultCode;
END_IF;

(* Diagnostics - Data logging uses UniLogic's Data Samplers — configured triggers (time-based or event-based) write structured records to Data Tables or SD card in CSV format. Exported files can be pushed via FTP or email. For cloud integration, UniCloud provides managed data ingestion. Simpler VisiLogic projects use HMI-triggered SD writes via custom ladder code. *)
fbDiag(
    ProcessRunning := bRunning,
    FaultActive := bFault,
    ProcessValue := rProcessValue,
    ControlOutput := rControlOutput
);

(* Watchdog - Detects frozen control *)
tonWatchdog(IN := bRunning AND NOT fbPID.OutputChanging, PT := T#10S);
IF tonWatchdog.Q THEN
    bFault := TRUE;
    nFaultCode := 99;  (* Watchdog fault *)
END_IF;

(* Reset Logic *)
IF bReset AND NOT bEmergencyStop THEN
    bFault := FALSE;
    nFaultCode := 0;
    fbDiag.ClearAlarms();
END_IF;

END_FUNCTION_BLOCK

Code Explanation:

1.Encapsulated function block follows Function block design in Unitronics uses - reusable across Packaging projects
2.FB_SafetyMonitor provides Guarding around rotating components including high/low limits
3.FB_RampGenerator prevents startup issues common in Bottle Filling systems
4.FB_PIDController tuned for Packaging: Kp=1.0, Ki=0.1
5.Watchdog timer detects frozen control - critical for intermediate to advanced Bottle Filling reliability
6.Diagnostic function block enables Data logging uses UniLogic's Data Samplers — configured triggers (time-based or event-based) write structured records to Data Tables or SD card in CSV format. Exported files can be pushed via FTP or email. For cloud integration, UniCloud provides managed data ingestion. Simpler VisiLogic projects use HMI-triggered SD writes via custom ladder code. and Alarm handling uses UniLogic's built-in Alarm Manager — configure alarm conditions in tables with severity, message text, and logging behaviour, and the engine handles detection, acknowledgement, history, and HMI display without custom code. VisiLogic uses a simpler alarm approach via HMI event handlers.

Best Practices

✓Follow Unitronics naming conventions: Unitronics projects use IDE-managed tag names rather than raw memory addressing.
✓Unitronics function design: Function block design in Unitronics uses user-defined FBs in UniLogic (more limi
✓Data organization: Unitronics uses its own tag database concept rather than IEC-standard data block
✓Function Blocks: Arrange blocks for clear left-to-right data flow
✓Function Blocks: Use consistent spacing and alignment for readability
✓Function Blocks: Label all inputs and outputs with meaningful names
✓Bottle Filling: Use minimum 10 readings for statistical fill tracking
✓Bottle Filling: Implement automatic re-zero of scales at regular intervals
✓Bottle Filling: Provide separate parameters for each product recipe
✓Debug with VisiLogic / UniLogic: Use the built-in simulator to reproduce issues before hardware visit
✓Safety: Guarding around rotating components
✓Use VisiLogic / UniLogic simulation tools to test Bottle Filling logic before deployment

Common Pitfalls to Avoid

⚠Function Blocks: Creating feedback loops without proper initialization
⚠Function Blocks: Connecting incompatible data types
⚠Function Blocks: Not considering execution order dependencies
⚠Unitronics common error: VisiLogic-to-UniLogic migration issues — not all projects convert cleanly
⚠Bottle Filling: Preventing dripping and stringing after fill cutoff
⚠Bottle Filling: Handling foaming products that give false level readings
⚠Neglecting to validate Bottle presence sensors (fiber optic or inductive) for container detection leads to control errors
⚠Insufficient comments make Function Blocks programs unmaintainable over time

Related Certifications

🏆Unitronics Certified Integrator

🏆UniLogic Developer Training

🏆Advanced Unitronics Programming Certification

Mastering Function Blocks for Bottle Filling applications using Unitronics VisiLogic / UniLogic requires understanding both the platform's capabilities and the specific demands of Packaging. This guide has provided comprehensive coverage of implementation strategies, working code examples, best practices, and common pitfalls to help you succeed with intermediate to advanced Bottle Filling projects.

Unitronics's 1% market share and moderate - us small-integrator market, oem machines, building automation demonstrate the platform's capability for demanding applications. The platform excels in Packaging applications where Bottle Filling reliability is critical.

By following the practices outlined in this guide—from proper program structure and Function Blocks best practices to Unitronics-specific optimizations—you can deliver reliable Bottle Filling systems that meet Packaging requirements.

Next Steps for Professional Development:

1. Certification: Pursue Unitronics Certified Integrator to validate your Unitronics expertise
2. Advanced Training: Consider UniLogic Developer Training for specialized Packaging applications
3. Hands-on Practice: Build Bottle Filling projects using Jazz 2 hardware
4. Stay Current: Follow VisiLogic / UniLogic updates and new Function Blocks features

Function Blocks Foundation:

Function Block Diagram (FBD) is a graphical programming language where functions and function blocks are represented as boxes connected by signal line...

The 3-6 weeks typical timeline for Bottle Filling projects will decrease as you gain experience with these patterns and techniques. Remember: Use minimum 10 readings for statistical fill tracking

For further learning, explore related topics including Temperature control, Pharmaceutical liquid filling, and Unitronics platform-specific features for Bottle Filling optimization.