The opening phase of an MES (Manufacturing Execution System) project sets direction for data ownership, integration boundaries and user acceptance. Alongside technical decisions, short structured conversations with operators at shift start help reveal whether the system will be usable on the floor.
1. First Walk With the Line Engineer (Week 1)
The software team should spend enough time observing the line and shift handovers for the agreed scope. Ask each station how the work is performed today, documenting current flows such as spreadsheets, paper tallies, messaging and verbal handovers. The MES should improve those processes against acceptance criteria rather than copy them blindly.
2. Data Model: 7 Core Entities
- Work Order: production order from customer demand
- Recipe / BOM: which raw materials + quantities + process
- Workstation: physical machine or manual labour point
- Operator: who, on which shift, with what authority
- Lot / Batch: a series produced under identical conditions
- Event: start, stop, defect, rework, scrap — timestamped
- Measurement: SPC data, quality control values
3. PLC Integration: Modbus, OPC UA or Direct?
Protocol support cannot be generalised from a PLC family name; verify the exact model, CPU, firmware and communications module. Choose Modbus, OPC UA, a vendor protocol or a secured gateway according to read-only data needs, cycle time and planned-downtime constraints.
4. Operator UI: Reduce Steps on the Floor
Test the operator screen on site for task order, error prevention and ergonomics. Choose target size, contrast and projected-capacitive or resistive touch according to gloves, lighting, distance and vibration; no single click count or panel technology fits every line.
5. Data Collection Speed vs. Accuracy
Keeping every PLC measurement indefinitely can create storage and query overhead. Set raw-data frequency, ring-buffer duration, aggregation windows and long-term retention from process dynamics, anomaly needs, audit scope and storage budget. Test the decision against data-loss and replay scenarios.
6. First Failure: User Resistance
After go-live, operators may keep a parallel spreadsheet for a while because of trust, missing functionality or habit. Rather than ordering them to stop, baseline the time and error rate of a workflow such as shift reporting, then compare the same measures after MES. Adoption still depends on usability, training and process ownership and should be monitored directly.
7. The Bridge to ERP
MES does not replace the ERP (SAP, Logo or Microsoft Dynamics); it integrates through a defined data contract. Orders, production instructions and completed-lot flows may use APIs, file transfer or message queues supported by the existing systems. Design retries, reconciliation and any human approval for synchronisation errors according to business impact.
8. Standards Compliance: ISO, IATF, FDA
Configure traceability and record-integrity requirements according to the applicable standard, industry, product and audit scope. Define separation of duties, timestamps, change history and retention for audit logs; installing MES alone does not create certification or regulatory compliance.
The output of the first 100 days is not merely a working screen; it is a verified data flow, acceptance criteria, a training plan and an operating model with clear ownership. Adoption and data quality must be monitored after technical go-live.