First-pass yield up 2.1pp on the dryer line.
A dairy producer replaces lab-delayed moisture checks with a real-time soft sensor, catching off-spec batches before they're packed.
What was happening before.
Off-spec batches were discovered too late to correct. Rework was costly and rejection rates depended heavily on which shift was running.
- Soft sensor must be explainable to a QA auditor.
- Cannot run closed-loop on a regulated product line — operators stay in control.
- Recommendation must use existing PLC tags only — no new instrumentation budget.
What we built, on what data.
- › Historian tags: inlet/outlet air temp, feed rate, exhaust humidity, atomiser pressure
- › Lab measurements: moisture, particle size
- › Batch records: SKU, start/end, operator
- 01Time-align lab samples with PLC tagsUsed Data Explorer to map historical lab moisture to the right point in the batch trajectory.
- 02Train a per-SKU soft sensorPredicts outlet moisture every 30 seconds with a calibrated confidence band.
- 03Push prediction to HMI tileOperator sees live moisture estimate, deviation from target, and a 15-minute forecast.
- 04Weekly recalibration with QAQA team re-labels drift days; model refits weekly with audit trail.
Who uses it, and where it fits in the day.
Every dryer operator on every shift uses the HMI tile. The QA lead owns the weekly recalibration. Engineering reviews drift monthly.
Quantified, with timeframe and caveats.
- R1First-pass yield up 2.1 percentage points across the audited line.
- R2Off-spec rework reduced by 38%.
- R3Operator-to-operator variability on moisture dropped meaningfully — measured by inter-shift sigma.
Operational outcome (proof rule): First-pass yield improved by 2.1 percentage points over six months on the audited line, with a 38% drop in off-spec rework.
"The moisture estimate is in front of the operator before the batch is half-dry. We adjust feed rate ourselves; we don't wait on the lab to tell us we already lost the batch."
Relevant for teams trying to…
F&B teams running batch dryers, evaporators, or any unit where the spec is confirmed off-line.
- A soft sensor only earns trust if its confidence band is visible. Hide the uncertainty and operators learn not to act on it.
- Per-SKU models beat one big model — small data, high variance between products.
- Pair model rollout with a one-hour shift training. Don't ship to an HMI without it.
Talk to an expert about a similar use case.
Tell us your unit and your KPI. We'll come back with what data you'd need and a realistic timeline based on Nordic Foods's rollout.