Consistency in Automation Achieved with Standardized Function Blocks

[Ahmet Ö.]

## Ensuring Consistency in Automation with Standardized Function Blocks

Cross-platform compatible, reusable function blocks in water and wastewater automation demonstrate that standardization is technically and economically feasible. This approach significantly reduces engineering costs and increases operational consistency.

### The Problem Encountered: Code Inconsistency

Despite using similar equipment, municipal water and wastewater facilities often experience code inconsistency due to custom coding in projects. With the use of various brands and models of PLC platforms, functions such as motor control, valve sequencing, and analog processing have to be re-written by engineers for each facility, which multiplies labor costs.

### The Solution: Cross-Platform Function Block Library

A comprehensive function block library specifically for water and wastewater applications was developed, compatible with three different PLC platforms:

• Rockwell ControlLogix/CompactLogix
• Rockwell Micro800
• Emerson PACSystems RX3i

Core function blocks include:

• Advanced motor/pump control (VFD integration, runtime tracking, predictive maintenance)
• Smart valve control (position verification, travel time monitoring)
• Analog signal optimization (scaling, totalization, alarm management)
• Pump rotation sequencer (lead-lag rotation, runtime equalization)

Each block includes automatic, manual, and Hand-Off-Auto control, comprehensive alarm management, runtime tracking for predictive maintenance, and a simulation mode for full factory acceptance tests.

### Design Approach: Platform-Specific Implementation

The code is not copied verbatim for each platform. Functional equivalence is prioritized, ensuring optimized behavior for each platform while maintaining the same user interface and functionality. Key design aspects:

• Comprehensive functionality, full-featured blocks instead of minimal structures
• Technical personnel can configure, no programming required
• Built-in intelligence to solve common scenarios within the block
• Simulation mode for risk-free testing

### Measured Successes

• 85% savings in engineering time (approximately 30 minutes for motor, valve, and analog)
• Significant reduction in the number of issues detected per project (from 15-20 to 2-3)
• Troubleshooting time reduced from 4 hours to 30-60 minutes
• Code similarity between facilities increased from 30% to 95%
• Operators adapt 40% faster when moving to a new facility

### Industry Applicability

This function block method enables standardization across different PLC manufacturers and facilities, offering flexibility and scalability to companies. Its expandable and adaptable structure makes it an ideal solution for engineering firms, municipal water utilities, and system integrators.

### Real-Life Example

Results from an 8 million gallons/day wastewater treatment plant project:

• 140 programming hours with traditional methods
• 24.5 hours with function blocks
• 115.5 hours of net savings
• FAT time reduced to 3 days (normally 5-7 days)
• Site commissioning 4 days (normally 7-10 days)
• Operator training 2 days (normally 4 days)

### Future Plans

The library will be further enhanced in version 3.0 with added features such as cybersecurity, cloud connectivity, advanced fault prediction, and energy optimization.

Standardization in water and wastewater automation is no longer just theoretical but has become a widely applicable approach. This innovation significantly reduces engineering costs while substantially increasing system reliability and operational consistency.