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Intermediate20 min readWater & Wastewater

B&R Industrial Automation Structured Text for Pump Control

Learn Structured Text programming for Pump Control using B&R Industrial Automation Automation Studio. Includes code examples, best practices, and step-by-step implementation guide for Water & Wastewater applications.

πŸ’»
Platform
Automation Studio
πŸ“Š
Complexity
Intermediate
⏱️
Project Duration
2-4 weeks

Learning to implement Structured Text for Pump Control using B&R Industrial Automation's Automation Studio is an essential skill for PLC programmers working in Water & Wastewater. This comprehensive guide walks you through the fundamentals, providing clear explanations and practical examples that you can apply immediately to real-world projects.

B&R Industrial Automation has established itself as Strong - Dominant with European machine builders in packaging, printing, plastics, making it a strategic choice for Pump Control applications. With 3% global market share and 5 popular PLC families including the X20 CPU series and X90 Mobile, B&R Industrial Automation provides the robust platform needed for intermediate complexity projects like Pump Control.

The Structured Text approach is particularly well-suited for Pump Control because complex calculations, data manipulation, advanced control algorithms, and when code reusability is important. This combination allows you to leverage powerful for complex logic while managing the typical challenges of Pump Control, including pressure regulation and pump sequencing.

Throughout this guide, you'll discover step-by-step implementation strategies, working code examples tested on Automation Studio, and industry best practices specific to Water & Wastewater. Whether you're programming your first Pump Control system or transitioning from another PLC platform, this guide provides the practical knowledge you need to succeed with B&R Industrial Automation Structured Text programming.

B&R Industrial Automation Automation Studio for Pump Control

B&R Automation Studio is an integrated development environment covering PLC programming, motion control, safety, HMI design, and robotics β€” all in a single project. Launched in the 1980s and refined continuously since, Automation Studio is the native tool for B&R's X20 and X90 controllers, APC industrial PCs, and Power Panel HMIs. The IDE's distinguishing feature is mapp Technology: pre-built software components for motion, axis coordination, operator interfaces, and diagnostics that reduce mach...

Platform Strengths for Pump Control:

  • Integrated PLC + motion + safety + HMI + robotics in one IDE

  • mapp Technology: pre-built motion and cockpit components

  • ARsim: fast offline simulation built into the IDE

  • Excellent for machine-builder OEM workflows


Unique ${brand.software} Features:

  • mapp Technology library: pre-built motion, cockpit, and safety components

  • ARsim integrated simulator runs Automation Runtime on the dev PC

  • IEC 61131-3 plus CFC, C, and C++ in the same project

  • Safety (SafeDESIGNER) and motion (mapp Motion) integrated into PLC workflow


Key Capabilities:

The Automation Studio environment excels at Pump Control applications through its integrated plc + motion + safety + hmi + robotics in one ide. This is particularly valuable when working with the 5 sensor types typically found in Pump Control systems, including Pressure transmitters, Flow meters, Level sensors.

Control Equipment for Pump Control:

  • Centrifugal pumps for high flow applications

  • Positive displacement pumps for metering

  • Submersible pumps for wet well applications

  • Booster pump systems for pressure maintenance


B&R Industrial Automation's controller families for Pump Control include:

  • X20 CPU series: Suitable for intermediate Pump Control applications

  • X90 Mobile: Suitable for intermediate Pump Control applications

  • APC2100: Suitable for intermediate Pump Control applications

  • APC3100: Suitable for intermediate Pump Control applications

Hardware Selection Guidance:

CPU selection on B&R ranges from the compact X20 series (entry-level machines with modest I/O counts) through X90 Mobile (for mobile equipment), APC2100 and APC3100 industrial PCs (high-performance machinery with integrated visualisation), and Power Panel C-series (combined PLC + HMI form factor). Selection depends on axis count, HMI complexity, and whether safety is required (Safety CPUs selectab...

Industry Recognition:

Strong - Dominant with European machine builders in packaging, printing, plastics. B&R Automation is a significant presence in automotive manufacturing, particularly for body-in-white automation, assembly line control, and end-of-line testing. mapp Technology function blocks for motion coordination and robotics handshaking are heavily used on complex multi-axis welding and rivetin...

Investment Considerations:

With $$$ pricing, B&R Industrial Automation positions itself in the premium segment. For Pump Control projects requiring intermediate skill levels and 2-4 weeks development time, the total investment includes hardware, software licensing, training, and ongoing support.

Understanding Structured Text for Pump Control

Structured Text (ST) is a high-level, text-based programming language defined in IEC 61131-3. It resembles Pascal and provides powerful constructs for complex algorithms, calculations, and data manipulation.

Execution Model:

Code executes sequentially from top to bottom within each program unit. Variables maintain state between scan cycles unless explicitly reset.

Core Advantages for Pump Control:

  • Powerful for complex logic: Critical for Pump Control when handling intermediate control logic

  • Excellent code reusability: Critical for Pump Control when handling intermediate control logic

  • Compact code representation: Critical for Pump Control when handling intermediate control logic

  • Good for algorithms and calculations: Critical for Pump Control when handling intermediate control logic

  • Familiar to software developers: Critical for Pump Control when handling intermediate control logic


Why Structured Text Fits Pump Control:

Pump Control systems in Water & Wastewater typically involve:

  • Sensors: Pressure transmitters for discharge and suction pressure, Flow meters (magnetic, ultrasonic, or vortex), Level transmitters for tank or wet well level

  • Actuators: Variable frequency drives (VFDs) for speed control, Motor starters (DOL or soft start), Control valves for flow regulation

  • Complexity: Intermediate with challenges including Preventing cavitation at low suction pressure


Control Strategies for Pump Control:

  • constant: Maintain fixed speed or output

  • pressure: PID control to maintain discharge pressure setpoint

  • flow: PID control to maintain flow rate setpoint


Programming Fundamentals in Structured Text:

Variables:
- declaration: VAR / VAR_INPUT / VAR_OUTPUT / VAR_IN_OUT / VAR_GLOBAL sections
- initialization: Variables can be initialized at declaration: Counter : INT := 0;
- constants: VAR CONSTANT section for read-only values

Operators:
- arithmetic: + - * / MOD (modulo)
- comparison: = <> < > <= >=
- logical: AND OR XOR NOT

ControlStructures:
- if: IF condition THEN statements; ELSIF condition THEN statements; ELSE statements; END_IF;
- case: CASE selector OF value1: statements; value2: statements; ELSE statements; END_CASE;
- for: FOR index := start TO end BY step DO statements; END_FOR;

Best Practices for Structured Text:

  • Use meaningful variable names with consistent naming conventions

  • Initialize all variables at declaration to prevent undefined behavior

  • Use enumerated types for state machines instead of magic numbers

  • Break complex expressions into intermediate variables for readability

  • Use functions for reusable calculations and function blocks for stateful operations


Common Mistakes to Avoid:

  • Using = instead of := for assignment (= is comparison)

  • Forgetting semicolons at end of statements

  • Integer division truncation - use REAL for decimal results

  • Infinite loops from incorrect WHILE/REPEAT conditions


Typical Applications:

1. PID control: Directly applicable to Pump Control
2. Recipe management: Related control patterns
3. Statistical calculations: Related control patterns
4. Data logging: Related control patterns

Understanding these fundamentals prepares you to implement effective Structured Text solutions for Pump Control using B&R Industrial Automation Automation Studio.

Implementing Pump Control with Structured Text

Pump control systems use PLCs to regulate liquid flow in industrial processes, water treatment, and building services. These systems manage pump operation, protect equipment, optimize energy use, and maintain process parameters.

This walkthrough demonstrates practical implementation using B&R Industrial Automation Automation Studio and Structured Text programming.

System Requirements:

A typical Pump Control implementation includes:

Input Devices (Sensors):
1. Pressure transmitters for discharge and suction pressure: Critical for monitoring system state
2. Flow meters (magnetic, ultrasonic, or vortex): Critical for monitoring system state
3. Level transmitters for tank or wet well level: Critical for monitoring system state
4. Temperature sensors for bearing and motor monitoring: Critical for monitoring system state
5. Vibration sensors for predictive maintenance: Critical for monitoring system state

Output Devices (Actuators):
1. Variable frequency drives (VFDs) for speed control: Primary control output
2. Motor starters (DOL or soft start): Supporting control function
3. Control valves for flow regulation: Supporting control function
4. Isolation valves (actuated for remote operation): Supporting control function
5. Check valves to prevent backflow: Supporting control function

Control Equipment:

  • Centrifugal pumps for high flow applications

  • Positive displacement pumps for metering

  • Submersible pumps for wet well applications

  • Booster pump systems for pressure maintenance


Control Strategies for Pump Control:

  • constant: Maintain fixed speed or output

  • pressure: PID control to maintain discharge pressure setpoint

  • flow: PID control to maintain flow rate setpoint

  • level: Control tank/wet well level within band


Implementation Steps:

Step 1: Characterize pump curve and system curve

In Automation Studio, characterize pump curve and system curve.

Step 2: Size VFD for application (constant torque vs. variable torque)

In Automation Studio, size vfd for application (constant torque vs. variable torque).

Step 3: Implement primary control loop (pressure, flow, or level)

In Automation Studio, implement primary control loop (pressure, flow, or level).

Step 4: Add pump protection logic (minimum flow, temperature, seal)

In Automation Studio, add pump protection logic (minimum flow, temperature, seal).

Step 5: Program lead/lag sequencing with alternation

In Automation Studio, program lead/lag sequencing with alternation.

Step 6: Implement soft start/stop ramps for smooth operation

In Automation Studio, implement soft start/stop ramps for smooth operation.


B&R Industrial Automation Function Design:

B&R is famous for mapp Technology: a library of pre-engineered FBs covering motion (mapp Motion), robotics (mapp Robotics), HMI (mapp View), alarming (mapp Alarm), recipes (mapp Recipe), data logging (mapp Logger), auditing (mapp Audit), and cybersecurity (mapp Security). OEMs build atop mapp components rather than reimplementing. Private libraries of OEM-specific FBs are common, maintained in versioned Automation Studio libraries.

Common Challenges and Solutions:

1. Preventing cavitation at low suction pressure

  • Solution: Structured Text addresses this through Powerful for complex logic.


2. Managing minimum flow requirements

  • Solution: Structured Text addresses this through Excellent code reusability.


3. Coordinating VFD speed with system pressure

  • Solution: Structured Text addresses this through Compact code representation.


4. Handling pump cycling with varying demand

  • Solution: Structured Text addresses this through Good for algorithms and calculations.


Safety Considerations:

  • Dry run protection using flow or level monitoring

  • Overtemperature protection for motor and bearings

  • Overload protection through current monitoring

  • Vibration trips for mechanical failure detection

  • Emergency stop with proper system depressurization


Performance Metrics:

  • Scan Time: Optimize for 5 inputs and 5 outputs

  • Memory Usage: Efficient data structures for X20 CPU series capabilities

  • Response Time: Meeting Water & Wastewater requirements for Pump Control

B&R Industrial Automation Diagnostic Tools:

Automation Studio integrated debugger with breakpoints in every IEC language,System Diagnostics Manager β€” System-wide runtime health with historical retention,mapp View Diagnostic pages β€” ready-made diagnostic overlays for machine operators,ARsim integrated simulator β€” full offline machine testing without hardware,Motion commissioning via mapp Motion oscilloscope β€” waveform view during axis tuning,Task Class Monitor β€” per-task cycle time, jitter, and deadline violation tracking,System Designer β€” topology view of controllers, X2X modules, and powerlink devices,Logger module (mapp Logger) for structured event capture with severity classification,Online comparison between running controller and project β€” finds out-of-sync changes,mapp Audit β€” full audit trail of operator actions (GAMP 5 / 21 CFR Part 11 aligned)

B&R Industrial Automation's Automation Studio provides tools for performance monitoring and optimization, essential for achieving the 2-4 weeks development timeline while maintaining code quality.

B&R Industrial Automation Structured Text Example for Pump Control

Complete working example demonstrating Structured Text implementation for Pump Control using B&R Industrial Automation Automation Studio. Follows B&R Industrial Automation naming conventions. Tested on X20 CPU series hardware.

(* B&R Industrial Automation Automation Studio - Pump Control Control *)
(* Structured Text Implementation for Water & Wastewater *)
(* B&R projects follow strict Hungarian-style naming with prefixes (b for *)

PROGRAM PRG_PUMP_CONTROL_Control

VAR
    (* State Machine Variables *)
    eState : E_PUMP_CONTROL_States := IDLE;
    bEnable : BOOL := FALSE;
    bFaultActive : BOOL := FALSE;

    (* Timers *)
    tonDebounce : TON;
    tonProcessTimeout : TON;
    tonFeedbackCheck : TON;

    (* Counters *)
    ctuCycleCounter : CTU;

    (* Process Variables *)
    rPressuretransmitters : REAL := 0.0;
    rCentrifugalpumps : REAL := 0.0;
    rSetpoint : REAL := 100.0;
END_VAR

VAR CONSTANT
    (* Water & Wastewater Process Parameters *)
    C_DEBOUNCE_TIME : TIME := T#500MS;
    C_PROCESS_TIMEOUT : TIME := T#30S;
    C_BATCH_SIZE : INT := 50;
END_VAR

(* Input Conditioning *)
tonDebounce(IN := bStartButton, PT := C_DEBOUNCE_TIME);
bEnable := tonDebounce.Q AND NOT bEmergencyStop AND bSafetyOK;

(* Main State Machine - Pattern: State machines on B&R are typically impl *)
CASE eState OF
    IDLE:
        rCentrifugalpumps := 0.0;
        ctuCycleCounter(RESET := TRUE);
        IF bEnable AND rPressuretransmitters > 0.0 THEN
            eState := STARTING;
        END_IF;

    STARTING:
        (* Ramp up output - Gradual start *)
        rCentrifugalpumps := MIN(rCentrifugalpumps + 5.0, rSetpoint);
        IF rCentrifugalpumps >= rSetpoint THEN
            eState := RUNNING;
        END_IF;

    RUNNING:
        (* Pump Control active - Pump control systems use PLCs to regulate liquid f *)
        tonProcessTimeout(IN := TRUE, PT := C_PROCESS_TIMEOUT);
        ctuCycleCounter(CU := bCyclePulse, PV := C_BATCH_SIZE);

        IF ctuCycleCounter.Q THEN
            eState := COMPLETE;
        ELSIF tonProcessTimeout.Q THEN
            bFaultActive := TRUE;
            eState := FAULT;
        END_IF;

    COMPLETE:
        rCentrifugalpumps := 0.0;
        (* Log production data - Data logging uses mapp Data and mapp Trend components β€” configured rather than coded. Structured logging of process variables, machine events, operator actions, and alarm history is handled by mapp components that write to local SD, networked SQL databases, or cloud endpoints. For regulated industries, mapp Audit provides GAMP 5 / 21 CFR Part 11 aligned electronic records. *)
        eState := IDLE;

    FAULT:
        rCentrifugalpumps := 0.0;
        (* Alarm handling uses mapp Alarm β€” a pre-engineered component with severity classes, group acknowledgement, historical archival, and operator-visible banner generation on mapp View HMIs. Alarm definitions live in structured configuration files rather than in code, simplifying translation into multiple operator languages. Integration with mapp Audit captures every acknowledgement for regulated industries. *)
        IF bFaultReset AND NOT bEmergencyStop THEN
            bFaultActive := FALSE;
            eState := IDLE;
        END_IF;
END_CASE;

(* Safety Override - Always executes *)
IF bEmergencyStop OR NOT bSafetyOK THEN
    rCentrifugalpumps := 0.0;
    eState := FAULT;
    bFaultActive := TRUE;
END_IF;

END_PROGRAM

Code Explanation:

  • 1.Enumerated state machine (State machines on B&R are typically implemented using the mapp State Engine component (graphical state-chart editor) or as CASE-of-INT in ST with strongly-typed state enumerations. For complex machines with parallel sub-sequences, SFC is common. State transition logging via mapp Logger is standard practice and supports incident analysis weeks after the fact.) for clear Pump Control sequence control
  • 2.Constants define Water & Wastewater-specific parameters: cycle time 30s, batch size
  • 3.Input conditioning with debounce timer prevents false triggers in industrial environment
  • 4.STARTING state implements soft-start ramp - prevents mechanical shock
  • 5.Process timeout detection identifies stuck conditions - critical for reliability
  • 6.Safety override section executes regardless of state - B&R Industrial Automation best practice for intermediate systems

Best Practices

  • βœ“Follow B&R Industrial Automation naming conventions: B&R projects follow strict Hungarian-style naming with prefixes (b for BOOL, n f
  • βœ“B&R Industrial Automation function design: B&R is famous for mapp Technology: a library of pre-engineered FBs covering moti
  • βœ“Data organization: B&R uses IEC 61131-3 global variable lists, PROGRAM VAR sections, and strongly-t
  • βœ“Structured Text: Use meaningful variable names with consistent naming conventions
  • βœ“Structured Text: Initialize all variables at declaration to prevent undefined behavior
  • βœ“Structured Text: Use enumerated types for state machines instead of magic numbers
  • βœ“Pump Control: Use PID with derivative on PV for pressure control
  • βœ“Pump Control: Implement soft start ramps even with VFD (200-500ms)
  • βœ“Pump Control: Add flow proving before considering pump operational
  • βœ“Debug with Automation Studio: Use Automation Studio breakpoints in ST β€” available across all IEC lan
  • βœ“Safety: Dry run protection using flow or level monitoring
  • βœ“Use Automation Studio simulation tools to test Pump Control logic before deployment

Common Pitfalls to Avoid

  • ⚠Structured Text: Using = instead of := for assignment (= is comparison)
  • ⚠Structured Text: Forgetting semicolons at end of statements
  • ⚠Structured Text: Integer division truncation - use REAL for decimal results
  • ⚠B&R Industrial Automation common error: Task class priority conflicts causing missed cycles in mid-priority application
  • ⚠Pump Control: Preventing cavitation at low suction pressure
  • ⚠Pump Control: Managing minimum flow requirements
  • ⚠Neglecting to validate Pressure transmitters for discharge and suction pressure leads to control errors
  • ⚠Insufficient comments make Structured Text programs unmaintainable over time

Related Certifications

πŸ†B&R Certified Specialist
πŸ†B&R Certified Professional
πŸ†ABB University Automation Studio certifications
πŸ†Advanced B&R Industrial Automation Programming Certification

Mastering Structured Text for Pump Control applications using B&R Industrial Automation Automation Studio requires understanding both the platform's capabilities and the specific demands of Water & Wastewater. This guide has provided comprehensive coverage of implementation strategies, working code examples, best practices, and common pitfalls to help you succeed with intermediate Pump Control projects.

B&R Industrial Automation's 3% market share and strong - dominant with european machine builders in packaging, printing, plastics demonstrate the platform's capability for demanding applications. The platform excels in Water & Wastewater applications where Pump Control reliability is critical.

By following the practices outlined in this guideβ€”from proper program structure and Structured Text best practices to B&R Industrial Automation-specific optimizationsβ€”you can deliver reliable Pump Control systems that meet Water & Wastewater requirements.

Next Steps for Professional Development:

1. Certification: Pursue B&R Certified Specialist to validate your B&R Industrial Automation expertise
2. Advanced Training: Consider B&R Certified Professional for specialized Water & Wastewater applications
3. Hands-on Practice: Build Pump Control projects using X20 CPU series hardware
4. Stay Current: Follow Automation Studio updates and new Structured Text features

Structured Text Foundation:

Structured Text (ST) is a high-level, text-based programming language defined in IEC 61131-3. It resembles Pascal and provides powerful constructs for...

The 2-4 weeks typical timeline for Pump Control projects will decrease as you gain experience with these patterns and techniques. Remember: Use PID with derivative on PV for pressure control

For further learning, explore related topics including Recipe management, Wastewater treatment, and B&R Industrial Automation platform-specific features for Pump Control optimization.