Case Study: Automating a Food Processing Line with Omron PLC + Invertek VFD
Automation is transforming food manufacturing — improving consistency, traceability, and uptime while lowering energy costs. This case study explains how a UK food processing plant modernised its conveyor and mixing line by integrating an Omron PLC with an Invertek Optidrive E3 VFD. The result: 35 % faster batch throughput, zero unplanned downtime for three months, and 12 % lower power consumption.
We’ll break down the project scope, hardware selection, integration steps, and the measurable ROI. Use our free tools — VFD Sizing Calculator • Cable Sizing Calculator • Braking Resistor Calculator • Motor Starter Selection Calculator — to plan your own upgrade.
Background: Legacy Equipment and Production Bottlenecks
The facility produces packaged sauces and dressings using multiple stainless-steel mixers feeding a conveyor filling line. Before automation, operators manually started motors, adjusted speeds via contactors, and relied on visual timing — causing:
- ⚙️ Inconsistent batch times and product texture
- ⚙️ Frequent conveyor jams due to mis-timed starts
- ⚙️ High energy peaks from direct-on-line starting
- ⚙️ No real-time production data or fault feedback
The engineering team sought a flexible PLC-VFD system capable of coordinating up to eight conveyors and three mixing motors under recipe-based control.
Objectives
- 🔹 Automate motor sequencing and speed control
- 🔹 Reduce operator intervention and manual timing
- 🔹 Improve product consistency and traceability
- 🔹 Lower energy usage through variable-speed drives
Solution Overview
The integrator designed a new control panel built around an Omron CP1L-M30DT1-D PLC and Invertek Optidrive E3 VFDs. The PLC provided 18 digital inputs and 12 transistor outputs for control logic, while the drives handled motor soft-starting, speed ramping, and load feedback. Communication between units used Modbus RTU over RS-485.
Hardware Summary
- 🧠 Controller: Omron CP1L-M30DT1-D PLC (30 I/O, 2 serial ports, 24 V DC logic)
- ⚡ Drives: Invertek ODE-3-120150-1F1A Optidrive E3 (2.2 kW, 230 V single-phase in / three-phase out)
- 📊 HMI: 7″ touchscreen for recipe selection and speed adjustment
- 🔌 Sensors: Photo-eyes, level switches, load cells via analog inputs
Design & Integration
1) Drive and Motor Sizing
Each motor’s load data was analysed using the VFD Sizing Calculator to ensure 15 % torque reserve. Drives were derated for the single-phase input configuration.
2) Cable Selection
Cable cross-section and shielding requirements were confirmed with the Cable Sizing Calculator, ensuring voltage drop < 3 % and full EMC compliance.
3) Control Logic
The Omron PLC executed sequential start logic using timers, interlocks, and Modbus speed references. Operators could initiate automatic cycles via HMI, with status LEDs indicating conveyor readiness.
4) Parameter Settings
- Acceleration time = 5 s
- Deceleration time = 3 s
- V/F mode for mixers; sensorless vector for conveyors
- Motor overload set to 110 %
Commissioning Process
The upgrade was executed during a single 48-hour production shutdown. Drives were pre-configured, then auto-tuned to each motor. The PLC logic was downloaded via CX-Programmer and tested with simulation before field start-up.
Verification Checks
- ✅ Conveyor speed synchronisation within ±2 %
- ✅ Emergency stop and STO tested per EN 60204-1
- ✅ Modbus communication validated at 115 kbps
- ✅ Power-on diagnostics logged in HMI event viewer
Results After 3 Months
| Metric | Before | After Omron + Invertek Upgrade |
|---|---|---|
| Batch Throughput | 420 kg/hr | 570 kg/hr (+35 %) |
| Unplanned Downtime | 10 h/month | 0 h/month |
| Energy Use (kWh/day) | 240 kWh | 211 kWh (−12 %) |
| Operator Adjustments | ~30/day | 8/day |
The system now maintains precise conveyor speed ratios across batches, automatically adjusts mixing times by recipe, and logs motor current to the HMI for predictive maintenance.
Operator Feedback
“The new Omron and Invertek control system has completely stabilised our process. Speeds stay consistent, and the start-up is smoother than ever. We no longer lose time retiming conveyors or clearing jams.” – Production Supervisor, Sauce Packaging Plant
Energy & Maintenance Benefits
- 💡 12 % lower electricity consumption through variable speed control
- 🛠 Belt life extended by 40 % due to soft starts
- 🔧 Motor temperature reduced by 8 °C on average
- 📉 Annual maintenance savings: ≈ £3,200
Data Integration & Traceability
The Omron PLC logs batch IDs, motor run times, and alarms to a USB data logger. Data is used for traceability and HACCP compliance. Each Invertek drive reports its status via Modbus, including temperature, frequency, and fault codes.
The line’s main PLC connects via Ethernet to a central SCADA dashboard for remote monitoring and email alerts to maintenance staff.
Return on Investment
- 💰 Total Cost: £27,000 (panel, hardware, commissioning)
- ⚡ Energy Savings: £2,900 per year
- 🧰 Maintenance Savings: £3,200 per year
- ⏱ Payback Period: ≈ 2.3 years
- 📈 ROI (5 years): 215 %
Technical Highlights
- ⚙️ Precise speed matching via analog signals (0–10 V)
- ⚙️ PID loops for mixer torque and temperature control
- ⚙️ Safe Torque Off (STO) wired through E-stop circuit
- ⚙️ Parameter copy via Invertek Optistick Smart tool
The engineering team verified drive heating and ventilation per IP20 specifications, ensuring ambient temperatures < 40 °C in control panels.
Lessons Learned
- 🔹 Integrate VFD status into PLC fault handling for instant diagnostics.
- 🔹 Size drives with 15–20 % margin — use the VFD Sizing Calculator.
- 🔹 Select proper shielded cable — use the Cable Sizing Calculator.
- 🔹 For rapid stop zones, dimension braking units using the Braking Resistor Calculator.
Future Expansion
Following success on the sauce line, the company plans to expand automation to three additional production lines. The new Omron NX1P2 series PLC will interface with larger Invertek Optidrive E3 and E3-IP66 drives for wash-down areas and integrated energy monitoring.
Conclusion
This project shows how combining Omron control logic with Invertek drive technology can dramatically enhance food processing efficiency. From consistent batch timing to energy savings and traceability, the system proved its value within months of commissioning.
Plan your own integration using our free engineering calculators below, and browse our wide range of Omron PLCs and Invertek drives for food, packaging, and automation applications.
- ⚙️ VFD Sizing Calculator
- ⚙️ VFD Cable Sizing Calculator
- ⚙️ Braking Resistor Calculator
- ⚙️ Motor Starter Selection Calculator
At Drive Outlet Megastore, we supply genuine Omron and Invertek automation equipment with 2-year warranty and next-day delivery. Contact our team today for a tailored quotation or technical assistance with your next automation project.
