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Intermediate20 min readWater & Wastewater

Inovance Structured Text for Pump Control

Learn Structured Text programming for Pump Control using Inovance InoProShop / AutoShop. Includes code examples, best practices, and step-by-step implementation guide for Water & Wastewater applications.

πŸ’»
Platform
InoProShop / AutoShop
πŸ“Š
Complexity
Intermediate
⏱️
Project Duration
2-4 weeks

Implementing Structured Text for Pump Control using Inovance InoProShop / AutoShop requires adherence to industry standards and proven best practices from Water & Wastewater. This guide compiles best practices from successful Pump Control deployments, Inovance programming standards, and Water & Wastewater requirements to help you deliver professional-grade automation solutions.

Inovance's position as High in China across textiles, packaging, lithium battery, EV manufacturing, elevators, robotics; growing in SE Asia and MEA means their platforms must meet rigorous industry requirements. Companies like AM600 users in municipal water systems and wastewater treatment have established proven patterns for Structured Text implementation that balance functionality, maintainability, and safety.

Best practices for Pump Control encompass multiple dimensions: proper handling of 5 sensor types, safe control of 5 different actuators, managing pressure regulation, and ensuring compliance with relevant industry standards. The Structured Text approach, when properly implemented, provides powerful for complex logic and excellent code reusability, both critical for intermediate projects.

This guide presents industry-validated approaches to Inovance Structured Text programming for Pump Control, covering code organization standards, documentation requirements, testing procedures, and maintenance best practices. You'll learn how leading companies structure their Pump Control programs, handle error conditions, and ensure long-term reliability in production environments.

Inovance InoProShop / AutoShop for Pump Control

Inovance ships InoProShop as its primary programming IDE for the AM600 / AM610 / H5U medium-PLC families and AutoShop for the Easy-series compact PLCs. InoProShop is built on the CODESYS 3.5 platform, which means engineers transferring from Beckhoff TwinCAT, WAGO e!Cockpit, or Schneider EcoStruxure Machine Expert will recognise the project tree, IEC 61131-3 editors, and visualisation tools immediately. AutoShop is a more traditional ladder-and-IL editor closer to compact-PLC tradition. Inovance'...

Platform Strengths for Pump Control:

  • CODESYS-based InoProShop for IEC 61131-3 compliance

  • Tight integration with Inovance servo drives and inverters

  • Strong motion, robotics, and elevator-control product lines

  • EtherCAT support across mid-tier and high-end CPUs


Unique ${brand.software} Features:

  • InoProShop built on CODESYS 3.5 β€” full IEC 61131-3 compliance

  • Native EtherCAT motion across mid-tier and high-end CPUs

  • Tight integration with Inovance servo drives, inverters, and HMIs

  • AutoShop for compact AC800 / Easy-series CPUs (lighter IDE)


Key Capabilities:

The InoProShop / AutoShop environment excels at Pump Control applications through its codesys-based inoproshop for iec 61131-3 compliance. 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


Inovance's controller families for Pump Control include:

  • AM600: Suitable for intermediate Pump Control applications

  • AM610: Suitable for intermediate Pump Control applications

  • H5U: Suitable for intermediate Pump Control applications

  • AC800: Suitable for intermediate Pump Control applications

Hardware Selection Guidance:

Inovance CPU choice ranges from Easy320 / Easy510 (compact, AutoShop-programmed, FX-style memory model) through AC800 (mid-range compact) to AM600 / AM610 / H5U (medium PLC with EtherCAT, OPC UA, redundant networking on H5U). AM600 is the volume product for OEM machinery; H5U is the choice for higher-axis-count motion applications and lithium-battery / EV manufacturing lines where EtherCAT and tig...

Industry Recognition:

High in China across textiles, packaging, lithium battery, EV manufacturing, elevators, robotics; growing in SE Asia and MEA. High in Chinese EV manufacturing β€” Inovance is a major automation supplier to BYD, NIO, and Tier 2/3 EV-component plants. AM600 + H5U with EtherCAT motion controls battery-cell assembly, module welding, pack assembly, and end-of-line test stations. Less common in Western Tier 1 automotive but appear...

Investment Considerations:

With $$ pricing, Inovance positions itself in the mid-range 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 Inovance InoProShop / AutoShop.

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 Inovance InoProShop / AutoShop 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 InoProShop / AutoShop, characterize pump curve and system curve.

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

In InoProShop / AutoShop, size vfd for application (constant torque vs. variable torque).

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

In InoProShop / AutoShop, implement primary control loop (pressure, flow, or level).

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

In InoProShop / AutoShop, add pump protection logic (minimum flow, temperature, seal).

Step 5: Program lead/lag sequencing with alternation

In InoProShop / AutoShop, program lead/lag sequencing with alternation.

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

In InoProShop / AutoShop, implement soft start/stop ramps for smooth operation.


Inovance Function Design:

InoProShop strongly favours function-block reuse via the Library Manager β€” Inovance ships standard libraries for motion, drives, HMI, OPC UA, and industry-specific applications (lithium-battery, EV, elevator). AutoShop reuse is open-coded via P-label subroutines. OEM machine-builders increasingly default to InoProShop / AM600 to access the FB 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 AM600 capabilities

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

Inovance Diagnostic Tools:

InoProShop online mode with full POU monitoring and breakpoint debug,EtherCAT diagnostics page with topology and slave status,Trace tool for analogue / motion signal capture,OPC UA server diagnostics page,Modbus communication trace utility,AutoShop online mode for legacy AC800 / Easy series,Inovance HMI integrated diagnostics for HMI-PLC binding faults,Servo-drive panel diagnostics with InoProShop drive-monitor view,EtherCAT slave-firmware update tool,Project compare tool for change tracking

Inovance's InoProShop / AutoShop provides tools for performance monitoring and optimization, essential for achieving the 2-4 weeks development timeline while maintaining code quality.

Inovance Structured Text Example for Pump Control

Complete working example demonstrating Structured Text implementation for Pump Control using Inovance InoProShop / AutoShop. Follows Inovance naming conventions. Tested on AM600 hardware.

(* Inovance InoProShop / AutoShop - Pump Control Control *)
(* Structured Text Implementation for Water & Wastewater *)
(* On InoProShop projects, conventions follow CODESYS / IEC norms β€” Pasca *)

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: InoProShop state machines typically use  *)
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 - InoProShop on AM600 / H5U supports SD-card logging via library FBs, plus OPC UA streaming for cloud / on-premises historians. Inovance HMIs add CSV logging at HMI tier. AutoShop projects rely on HMI-tier logging exclusively. *)
        eState := IDLE;

    FAULT:
        rCentrifugalpumps := 0.0;
        (* InoProShop alarms are typically defined in the visualisation alarm-configuration page with severity, latching, and acknowledgement behaviour configured per alarm. The runtime maintains active and historical alarm lists. AutoShop projects fall back to M-flag banks with HMI-side alarm logging. *)
        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 (InoProShop state machines typically use IEC SFC steps with action blocks per step, or a state-enum-and-CASE pattern in Structured Text. SFC dominates production-line sequencers; CASE patterns dominate axis-control state and recipe-routing logic. AutoShop projects fall back to FX-style SFC step memory (S0..S511) or D-register integer state.) 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 - Inovance best practice for intermediate systems

Best Practices

  • βœ“Follow Inovance naming conventions: On InoProShop projects, conventions follow CODESYS / IEC norms β€” PascalCase for
  • βœ“Inovance function design: InoProShop strongly favours function-block reuse via the Library Manager β€” Inova
  • βœ“Data organization: InoProShop uses GVLs and persistent variables for shared data. AutoShop uses D /
  • 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 InoProShop / AutoShop: Use InoProShop's online mode to set breakpoints in POUs and step throu
  • βœ“Safety: Dry run protection using flow or level monitoring
  • βœ“Use InoProShop / AutoShop 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
  • ⚠Inovance common error: EtherCAT slave order mismatch after physical re-cabling β€” slave addressing break
  • ⚠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†Inovance Certified Engineer
πŸ†InoProShop / AutoShop training certificates
πŸ†EV / Lithium Battery automation specialist tracks
πŸ†Advanced Inovance Programming Certification

Mastering Structured Text for Pump Control applications using Inovance InoProShop / AutoShop 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.

Inovance's ~2% global, top-3 in China market share and high in china across textiles, packaging, lithium battery, ev manufacturing, elevators, robotics; growing in se asia and mea 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 Inovance-specific optimizationsβ€”you can deliver reliable Pump Control systems that meet Water & Wastewater requirements.

Next Steps for Professional Development:

1. Certification: Pursue Inovance Certified Engineer to validate your Inovance expertise
2. Advanced Training: Consider InoProShop / AutoShop training certificates for specialized Water & Wastewater applications
3. Hands-on Practice: Build Pump Control projects using AM600 hardware
4. Stay Current: Follow InoProShop / AutoShop 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 Inovance platform-specific features for Pump Control optimization.