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Intermediate15 min readWater & Wastewater

Unitronics Counters for Pump Control

Learn Counters programming for Pump Control using Unitronics VisiLogic / UniLogic. Includes code examples, best practices, and step-by-step implementation guide for Water & Wastewater applications.

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

Troubleshooting Counters programs for Pump Control in Unitronics's VisiLogic / UniLogic requires systematic diagnostic approaches and deep understanding of common failure modes. This guide equips you with proven troubleshooting techniques specific to Pump Control applications, helping you quickly identify and resolve issues in production environments.

Unitronics's 1% market presence means Unitronics Counters programs power thousands of Pump Control systems globally. This extensive deployment base has revealed common issues and effective troubleshooting strategies. Understanding these patterns accelerates problem resolution from hours to minutes, minimizing downtime in Water & Wastewater operations.

Common challenges in Pump Control systems include pressure regulation, pump sequencing, and energy optimization. When implemented with Counters, additional considerations include limited to counting operations, requiring specific diagnostic approaches. Unitronics's diagnostic tools in VisiLogic / UniLogic provide powerful capabilities, but knowing exactly which tools to use for specific symptoms dramatically improves troubleshooting efficiency.

This guide walks through systematic troubleshooting procedures, from initial symptom analysis through root cause identification and permanent correction. You'll learn how to leverage VisiLogic / UniLogic's diagnostic features, interpret system behavior in Pump Control contexts, and apply proven fixes to common Counters implementation issues specific to Unitronics platforms.

Unitronics VisiLogic / UniLogic for Pump Control

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 β€” the sim...

Platform Strengths for Pump Control:

  • 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 Pump Control 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 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


Unitronics's controller families for Pump Control include:

  • Jazz 2: Suitable for intermediate Pump Control applications

  • Samba 7": Suitable for intermediate Pump Control applications

  • Vision V350: Suitable for intermediate Pump Control applications

  • Vision V570: Suitable for intermediate Pump Control 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 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 Counters for Pump Control

PLC counters track the number of events or items. They increment or decrement on input transitions and compare against preset values.

Execution Model:

For Pump Control applications, Counters offers significant advantages when counting parts, cycles, events, or maintaining production totals.

Core Advantages for Pump Control:

  • Essential for production tracking: Critical for Pump Control when handling intermediate control logic

  • Simple to implement: Critical for Pump Control when handling intermediate control logic

  • Reliable and accurate: Critical for Pump Control when handling intermediate control logic

  • Easy to understand: Critical for Pump Control when handling intermediate control logic

  • Widely used: Critical for Pump Control when handling intermediate control logic


Why Counters 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 Counters:

Counters in VisiLogic / UniLogic follows these key principles:

1. Structure: Counters organizes code with simple to implement
2. Execution: Scan cycle integration ensures 5 sensor inputs are processed reliably
3. Data Handling: Proper data types for 5 actuator control signals

Best Practices for Counters:

  • Debounce mechanical switch inputs before counting

  • Use high-speed counters for pulses faster than scan time

  • Implement overflow detection for long-running counters

  • Store counts to retentive memory if needed across power cycles

  • Add counter values to HMI for operator visibility


Common Mistakes to Avoid:

  • Counting level instead of edge - multiple counts from one event

  • Not debouncing noisy inputs causing false counts

  • Using standard counters for high-speed applications

  • Integer overflow causing count wrap-around


Typical Applications:

1. Bottle counting: Directly applicable to Pump Control
2. Conveyor tracking: Related control patterns
3. Production totals: Related control patterns
4. Batch counting: Related control patterns

Understanding these fundamentals prepares you to implement effective Counters solutions for Pump Control using Unitronics VisiLogic / UniLogic.

Implementing Pump Control with Counters

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 Unitronics VisiLogic / UniLogic and Counters 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 VisiLogic / UniLogic, characterize pump curve and system curve.

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

In VisiLogic / UniLogic, size vfd for application (constant torque vs. variable torque).

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

In VisiLogic / UniLogic, implement primary control loop (pressure, flow, or level).

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

In VisiLogic / UniLogic, add pump protection logic (minimum flow, temperature, seal).

Step 5: Program lead/lag sequencing with alternation

In VisiLogic / UniLogic, program lead/lag sequencing with alternation.

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

In VisiLogic / UniLogic, implement soft start/stop ramps for smooth operation.


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 cavitation at low suction pressure

  • Solution: Counters addresses this through Essential for production tracking.


2. Managing minimum flow requirements

  • Solution: Counters addresses this through Simple to implement.


3. Coordinating VFD speed with system pressure

  • Solution: Counters addresses this through Reliable and accurate.


4. Handling pump cycling with varying demand

  • Solution: Counters addresses this through Easy to understand.


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 Jazz 2 capabilities

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

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 β€” 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 β€” 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 β€” 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 2-4 weeks development timeline while maintaining code quality.

Unitronics Counters Example for Pump Control

Complete working example demonstrating Counters implementation for Pump Control using Unitronics VisiLogic / UniLogic. Follows Unitronics naming conventions. Tested on Jazz 2 hardware.

// Unitronics VisiLogic / UniLogic - Pump Control Control
// Counters Implementation for Water & Wastewater
// Unitronics projects use IDE-managed tag names rather than ra

// ============================================
// Variable Declarations
// ============================================
VAR
    bEnable : BOOL := FALSE;
    bEmergencyStop : BOOL := FALSE;
    rPressuretransmitters : REAL;
    rCentrifugalpumps : REAL;
END_VAR

// ============================================
// Input Conditioning - Pressure transmitters for discharge and suction pressure
// ============================================
// Standard input processing
IF rPressuretransmitters > 0.0 THEN
    bEnable := TRUE;
END_IF;

// ============================================
// Safety Interlock - Dry run protection using flow or level monitoring
// ============================================
IF bEmergencyStop THEN
    rCentrifugalpumps := 0.0;
    bEnable := FALSE;
END_IF;

// ============================================
// Main Pump Control Control Logic
// ============================================
IF bEnable AND NOT bEmergencyStop THEN
    // Pump control systems use PLCs to regulate liquid flow in ind
    rCentrifugalpumps := rPressuretransmitters * 1.0;

    // Process monitoring
    // Add specific control logic here
ELSE
    rCentrifugalpumps := 0.0;
END_IF;

Code Explanation:

  • 1.Counters structure optimized for Pump Control in Water & Wastewater applications
  • 2.Input conditioning handles Pressure transmitters for discharge and suction pressure signals
  • 3.Safety interlock ensures Dry run protection using flow or level monitoring always takes priority
  • 4.Main control implements Pump control systems use PLCs to regulat
  • 5.Code runs every scan cycle on Jazz 2 (typically 5-20ms)

Best Practices

  • βœ“Follow Unitronics naming conventions: Unitronics projects use IDE-managed tag names rather than raw memory addressing.
  • βœ“Unitronics function design: Function block design in Unitronics uses user-defined FBs in UniLogic (more limi
  • βœ“Data organization: Unitronics uses its own tag database concept rather than IEC-standard data block
  • βœ“Counters: Debounce mechanical switch inputs before counting
  • βœ“Counters: Use high-speed counters for pulses faster than scan time
  • βœ“Counters: Implement overflow detection for long-running counters
  • 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 VisiLogic / UniLogic: Use the built-in simulator to reproduce issues before hardware visit
  • βœ“Safety: Dry run protection using flow or level monitoring
  • βœ“Use VisiLogic / UniLogic simulation tools to test Pump Control logic before deployment

Common Pitfalls to Avoid

  • ⚠Counters: Counting level instead of edge - multiple counts from one event
  • ⚠Counters: Not debouncing noisy inputs causing false counts
  • ⚠Counters: Using standard counters for high-speed applications
  • ⚠Unitronics common error: VisiLogic-to-UniLogic migration issues β€” not all projects convert cleanly
  • ⚠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 Counters programs unmaintainable over time

Related Certifications

πŸ†Unitronics Certified Integrator
πŸ†UniLogic Developer Training

Mastering Counters for Pump Control applications using Unitronics VisiLogic / UniLogic 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.

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 Water & Wastewater applications where Pump Control reliability is critical.

By following the practices outlined in this guideβ€”from proper program structure and Counters best practices to Unitronics-specific optimizationsβ€”you can deliver reliable Pump Control systems that meet Water & Wastewater 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 Water & Wastewater applications
3. Hands-on Practice: Build Pump Control projects using Jazz 2 hardware
4. Stay Current: Follow VisiLogic / UniLogic updates and new Counters features

Counters Foundation:

PLC counters track the number of events or items. They increment or decrement on input transitions and compare against preset values....

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 Conveyor tracking, Wastewater treatment, and Unitronics platform-specific features for Pump Control optimization.