Electronics & Embedded

Engineering project

Industrial PLC Controller for Water Treatment

Custom PLC-based control system for 50MLD water treatment plant with online chemical dosing and SCADA.

PLCSCADAModbusWater Treatment

Project brief

Automation control system for a 50 million-liters-per-day municipal water treatment plant including intake pumping, coagulation/flocculation chemical dosing, sedimentation, filtration, and chlorination stages. The system features online water quality measurement and automatic chemical feed adjustment to maintain treated water quality within NEQS standards.

The record focuses on process automation from intake through treatment monitoring. The explanation adds no water-quality certification or operational savings.

The engineering challenge

Sequence water-treatment stages while responding to quality measurements, tank levels, and equipment states.

Engineering approach

  1. Map process instrumentation and actuators into PLC control functions.
  2. Coordinate pumping, dosing, and treatment-stage interlocks.
  3. Preserve process trends and alarm context through the SCADA historian.

Features & capabilities

  • Control of 120 actuators: pumps, valves, blowers, dosing pumps
  • Online analyzers: turbidity, pH, chlorine residual, fluoride, TDS
  • Automatic chemical dosing: alum, lime, chlorine based on water quality
  • Surge tank level control with variable speed drive optimization
  • SCADA with 15-minute data historian (5-year retention)
  • Remote monitoring via secure 4G cellular link with VPN
  • Alarm management: 450+ alarms with priority classification
  • Energy optimization: pump scheduling based on tariff periods

Software & engineering tools

Allen-Bradley PLC (ControlLogix), RSView32 SCADA, Modbus RTU/TCP, 4G cellular, ProSoft communications modules