Intermediate15 min readIndustrial Manufacturing

ABB Function Blocks for Motor Control

Learn Function Blocks programming for Motor Control using ABB Automation Builder. Includes code examples, best practices, and step-by-step implementation guide for Industrial Manufacturing applications.

💻
Platform
Automation Builder
📊
Complexity
Beginner to Intermediate
⏱️
Project Duration
1-3 weeks
Implementing Function Blocks for Motor Control using ABB Automation Builder 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 Motor Control deployments. ABB's platform serves Medium - Strong in power generation, mining, and marine applications, providing the proven foundation for Motor Control implementations. The Automation Builder environment supports 5 programming languages, with Function Blocks being particularly effective for Motor Control because process control, continuous operations, modular programming, and signal flow visualization. Practical implementation requires understanding not just language syntax, but how ABB's execution model handles 5 sensor inputs and 5 actuator outputs in real-time. Real Motor Control projects in Industrial Manufacturing face practical challenges including soft start implementation, overload protection, and integration with existing systems. Success requires balancing visual representation of signal flow against can become cluttered with complex logic, while meeting 1-3 weeks project timelines typical for Motor Control implementations. This guide provides step-by-step implementation guidance, complete working examples tested on AC500, practical design patterns, and real-world troubleshooting scenarios. You'll learn the pragmatic approaches that experienced integrators use to deliver reliable Motor Control systems on schedule and within budget.

ABB Automation Builder for Motor Control

Automation Builder provides ABB's unified environment for AC500 PLC programming, drive configuration, and HMI development. Built on CODESYS V3 with ABB-specific enhancements. Strength lies in seamless drive integration with ACS880 and other families....

Platform Strengths for Motor Control:

  • Excellent for robotics integration

  • Strong in power and utilities

  • Robust hardware for harsh environments

  • Good scalability


Unique ${brand.software} Features:

  • Integrated drive configuration for ACS880, ACS580 drives

  • Extensive application libraries: HVAC, pumping, conveying, crane control

  • Safety programming for AC500-S within standard project

  • Panel Builder 600 HMI development integrated


Key Capabilities:

The Automation Builder environment excels at Motor Control applications through its excellent for robotics integration. This is particularly valuable when working with the 5 sensor types typically found in Motor Control systems, including Current sensors, Vibration sensors, Temperature sensors.

Control Equipment for Motor Control:

  • Motor control centers (MCCs)

  • AC induction motors (NEMA/IEC frame)

  • Synchronous motors for high efficiency

  • DC motors for precise speed control


ABB's controller families for Motor Control include:

  • AC500: Suitable for beginner to intermediate Motor Control applications

  • AC500-eCo: Suitable for beginner to intermediate Motor Control applications

  • AC500-S: Suitable for beginner to intermediate Motor Control applications

Hardware Selection Guidance:

PM554 entry-level for simple applications. PM564 mid-range for OEM machines. PM573 high-performance for complex algorithms. PM5 series latest generation with cloud connectivity. AC500-S for integrated safety....

Industry Recognition:

Medium - Strong in power generation, mining, and marine applications. AC500 coordinating VFD-controlled motors with ACS880 drives. Energy optimization reducing consumption 25-40%. Robot integration via ABB robot interfaces. Press line automation with AC500-S safety....

Investment Considerations:

With $$ pricing, ABB positions itself in the mid-range segment. For Motor Control projects requiring beginner skill levels and 1-3 weeks development time, the total investment includes hardware, software licensing, training, and ongoing support.

Understanding Function Blocks for Motor Control

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 Motor Control:

  • Visual representation of signal flow: Critical for Motor Control when handling beginner to intermediate control logic

  • Good for modular programming: Critical for Motor Control when handling beginner to intermediate control logic

  • Reusable components: Critical for Motor Control when handling beginner to intermediate control logic

  • Excellent for process control: Critical for Motor Control when handling beginner to intermediate control logic

  • Good for continuous operations: Critical for Motor Control when handling beginner to intermediate control logic


Why Function Blocks Fits Motor Control:

Motor Control systems in Industrial Manufacturing typically involve:

  • Sensors: Current transformers for motor current monitoring, RTD or thermocouple for motor winding temperature, Vibration sensors for bearing monitoring

  • Actuators: Contactors for direct-on-line starting, Soft starters for reduced voltage starting, Variable frequency drives for speed control

  • Complexity: Beginner to Intermediate with challenges including Managing starting current within supply limits


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 Motor Control
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 Motor Control using ABB Automation Builder.

Implementing Motor Control with Function Blocks

Motor control systems use PLCs to start, stop, and regulate electric motors in industrial applications. These systems provide protection, speed control, and coordination for motors ranging from fractional horsepower to thousands of horsepower.

This walkthrough demonstrates practical implementation using ABB Automation Builder and Function Blocks programming.

System Requirements:

A typical Motor Control implementation includes:

Input Devices (Sensors):
1. Current transformers for motor current monitoring: Critical for monitoring system state
2. RTD or thermocouple for motor winding temperature: Critical for monitoring system state
3. Vibration sensors for bearing monitoring: Critical for monitoring system state
4. Speed encoders or tachometers: Critical for monitoring system state
5. Torque sensors for load monitoring: Critical for monitoring system state

Output Devices (Actuators):
1. Contactors for direct-on-line starting: Primary control output
2. Soft starters for reduced voltage starting: Supporting control function
3. Variable frequency drives for speed control: Supporting control function
4. Brakes (mechanical or dynamic): Supporting control function
5. Starters (star-delta, autotransformer): Supporting control function

Control Equipment:

  • Motor control centers (MCCs)

  • AC induction motors (NEMA/IEC frame)

  • Synchronous motors for high efficiency

  • DC motors for precise speed control


Control Strategies for Motor Control:

1. Primary Control: Industrial motor control using PLCs for start/stop, speed control, and protection of electric motors.
2. Safety Interlocks: Preventing Soft start implementation
3. Error Recovery: Handling Overload protection

Implementation Steps:

Step 1: Calculate motor starting current and verify supply capacity

In Automation Builder, calculate motor starting current and verify supply capacity.

Step 2: Select starting method based on motor size and load requirements

In Automation Builder, select starting method based on motor size and load requirements.

Step 3: Configure motor protection with correct thermal curve

In Automation Builder, configure motor protection with correct thermal curve.

Step 4: Implement control logic for start/stop with proper interlocks

In Automation Builder, implement control logic for start/stop with proper interlocks.

Step 5: Add speed control loop if VFD is used

In Automation Builder, add speed control loop if vfd is used.

Step 6: Configure acceleration and deceleration ramps

In Automation Builder, configure acceleration and deceleration ramps.


ABB Function Design:

Standard FB structure with VAR_INPUT/OUTPUT/VAR. Methods extend functionality. ABB application libraries provide tested FBs. Drive FBs wrap drive parameter access.

Common Challenges and Solutions:

1. Managing starting current within supply limits

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


2. Coordinating acceleration with driven load requirements

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


3. Protecting motors from frequent starting (thermal cycling)

  • Solution: Function Blocks addresses this through Reusable components.


4. Handling regenerative energy during deceleration

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


Safety Considerations:

  • Proper machine guarding for rotating equipment

  • Emergency stop functionality with safe torque off

  • Lockout/tagout provisions for maintenance

  • Arc flash protection and PPE requirements

  • Proper grounding and bonding


Performance Metrics:

  • Scan Time: Optimize for 5 inputs and 5 outputs

  • Memory Usage: Efficient data structures for AC500 capabilities

  • Response Time: Meeting Industrial Manufacturing requirements for Motor Control

ABB Diagnostic Tools:

Online monitoring with live values,Watch window with expressions,Breakpoints for inspection,Drive diagnostics showing fault history,Communication diagnostics for network statistics

ABB's Automation Builder provides tools for performance monitoring and optimization, essential for achieving the 1-3 weeks development timeline while maintaining code quality.

ABB Function Blocks Example for Motor Control

Complete working example demonstrating Function Blocks implementation for Motor Control using ABB Automation Builder. Follows ABB naming conventions. Tested on AC500 hardware.

(* ABB Automation Builder - Motor Control Control *)
(* Reusable Function Blocks Implementation *)
(* Standard FB structure with VAR_INPUT/OUTPUT/VAR. Methods ext *)

FUNCTION_BLOCK FB_MOTOR_CONTROL_Controller

VAR_INPUT
    bEnable : BOOL;                  (* Enable control *)
    bReset : BOOL;                   (* Fault reset *)
    rProcessValue : REAL;            (* Current transformers for motor current monitoring *)
    rSetpoint : REAL := 100.0;  (* Target value *)
    bEmergencyStop : BOOL;           (* Safety input *)
END_VAR

VAR_OUTPUT
    rControlOutput : REAL;           (* Contactors for direct-on-line starting *)
    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;         (* ST_Alarm structure with bActive, bAcknowledged, dtActivation, nCode, sMessage. Array of alarms with detection and acknowledgment logic. Integration with ABB alarm libraries. *)

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

(* Safety Monitor - Proper machine guarding for rotating equipment *)
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,  (* Industrial Manufacturing 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 - Emergency stop functionality with safe torque off *)
    rControlOutput := 0.0;
    bRunning := FALSE;
    bFault := NOT bEnable;  (* Only fault if not intentional stop *)
    nFaultCode := fbSafety.FaultCode;
END_IF;

(* Diagnostics - Circular buffer with ST_LogRecord. Write index with modulo wrap. Triggered capture with pre/post samples. File export using file system library. *)
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 Standard FB structure with VAR_INPUT/OUT - reusable across Industrial Manufacturing projects
  • 2.FB_SafetyMonitor provides Proper machine guarding for rotating equipment including high/low limits
  • 3.FB_RampGenerator prevents startup issues common in Motor Control systems
  • 4.FB_PIDController tuned for Industrial Manufacturing: Kp=1.0, Ki=0.1
  • 5.Watchdog timer detects frozen control - critical for beginner to intermediate Motor Control reliability
  • 6.Diagnostic function block enables Circular buffer with ST_LogRecord. Write index with modulo wrap. Triggered capture with pre/post samples. File export using file system library. and ST_Alarm structure with bActive, bAcknowledged, dtActivation, nCode, sMessage. Array of alarms with detection and acknowledgment logic. Integration with ABB alarm libraries.

Best Practices

  • Follow ABB naming conventions: g_ prefix for globals. i_/q_ for FB I/O. Type prefixes: b=BOOL, n=INT, r=REAL, s
  • ABB function design: Standard FB structure with VAR_INPUT/OUTPUT/VAR. Methods extend functionality. A
  • Data organization: DUTs define structures. GVLs group related data. Retain attribute preserves vari
  • 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
  • Motor Control: Verify motor running with current or speed feedback, not just contactor status
  • Motor Control: Implement minimum off time between starts for motor cooling
  • Motor Control: Add phase loss and phase reversal protection
  • Debug with Automation Builder: Use structured logging to controller log
  • Safety: Proper machine guarding for rotating equipment
  • Use Automation Builder simulation tools to test Motor Control 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
  • ABB common error: Exception 'AccessViolation': Null pointer access
  • Motor Control: Managing starting current within supply limits
  • Motor Control: Coordinating acceleration with driven load requirements
  • Neglecting to validate Current transformers for motor current monitoring leads to control errors
  • Insufficient comments make Function Blocks programs unmaintainable over time

Related Certifications

🏆ABB Automation Certification
🏆Advanced ABB Programming Certification
Mastering Function Blocks for Motor Control applications using ABB Automation Builder requires understanding both the platform's capabilities and the specific demands of Industrial Manufacturing. This guide has provided comprehensive coverage of implementation strategies, working code examples, best practices, and common pitfalls to help you succeed with beginner to intermediate Motor Control projects. ABB's 8% market share and medium - strong in power generation, mining, and marine applications demonstrate the platform's capability for demanding applications. The platform excels in Industrial Manufacturing applications where Motor Control reliability is critical. By following the practices outlined in this guide—from proper program structure and Function Blocks best practices to ABB-specific optimizations—you can deliver reliable Motor Control systems that meet Industrial Manufacturing requirements. **Next Steps for Professional Development:** 1. **Certification**: Pursue ABB Automation Certification to validate your ABB expertise 3. **Hands-on Practice**: Build Motor Control projects using AC500 hardware 4. **Stay Current**: Follow Automation Builder 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 1-3 weeks typical timeline for Motor Control projects will decrease as you gain experience with these patterns and techniques. Remember: Verify motor running with current or speed feedback, not just contactor status For further learning, explore related topics including Temperature control, Fan systems, and ABB platform-specific features for Motor Control optimization.