This article is for plant managers, production managers, continuous improvement and maintenance leaders who have to decide where the next productivity effort goes: a TPM push, a lean program, training, or new equipment. Each of those choices commits people and budget for months. The choice is only as good as the picture of lost time behind it, and on most lines that picture is missing its most frequent item: the short stop.
- Short stops are cleared in seconds and rarely reach the manual log.
- A plan built on that log leans toward breakdowns by default.
- A few weeks of automatic stop records size each loss in hours.
- Size TPM, lean, training and technology first, then choose.
Why short stops rarely reach the manual log
A manual downtime log is filled in by people who are busy running the line. When a sensor faults, a part jams in a feeder or a label misfeeds, the operator clears it in under a minute and restarts. Nobody walks to the terminal or the paper sheet for that. The stop was real, the line did not produce, but the record says nothing happened.
Several mechanisms push in the same direction:
- Recording thresholds. Many plants only ask for a reason above a few minutes. Everything below the threshold disappears by design.
- End of shift recall. When the log is completed at the end of the shift, people remember the breakdown that called maintenance, not the twenty restarts in between.
- Rounding. Durations get rounded to 5, 10 or 15 minutes. Long stops are inflated, short ones vanish.
- The “other” bucket. When the list of reasons does not match what happened, the stop goes into “other” or “misc”, and nobody can act on it.
The result is a log that describes breakdowns and changeovers reasonably well and says very little about minor stops and idling. Yet those are the losses that repeat dozens of times a shift. A plan built on that log will naturally lean toward breakdown work, because breakdowns are what the data shows.
Six strategies, one question first: Doug Hanawalt’s article
Doug Hanawalt, Lead Productivity Improvement Specialist at Purdue MEP, sets out six levers in Practical Strategies for Improving Manufacturing Productivity: adopt lean, optimize processes and workflows, focus on workforce development, implement Total Productive Maintenance, implement technology, and measure. It is a clear, practical list, and the order of the last item is worth noticing.
In his section on measurement, he asks: “How do you know if you are continuously improving if you don’t measure first?”
Two other points in his article connect directly to short stops. In the TPM section, he lists “idling and minor stops” among the six big losses and makes the case for preventing breakdowns rather than reacting to them. He also notes that three minutes of downtime per hour adds up to 12.5 days lost per year. In the technology section, he points out that machine monitoring has become more affordable than in the past. His article does not discuss any specific product, and the approach described below is TEEPTRAK’s own reading of how to apply the “measure first” principle to stop data.
What a few weeks of automatic stop records show
Automatic stop records capture every stop from a machine signal, with a start time and an end time, whether it lasts eight seconds or two hours. Operators still add the reason, but they no longer decide whether a stop exists. Over a few weeks, that changes the picture in three ways.
First, the count of stops goes up, often sharply, because short stops appear. Second, the distribution becomes visible: you can see how much time sits in stops under two minutes, between two and ten minutes, and above ten minutes. Third, patterns emerge by shift, product, hour of the day and machine, which a monthly log summary flattens out.
Why a few weeks rather than a few days? Because you want to cover the normal product mix, all shifts, and at least a couple of changeovers per format. Three to four weeks is usually enough on a line that runs a stable mix. A line with long campaigns may need longer to see every product.
From stop records to TPM and lean priorities
The point of the stop study is not a better chart. It is to size each candidate lever in hours before choosing one. The table below shows how typical patterns in the records map to the strategies in Doug Hanawalt’s list. The patterns are examples, not results from a specific plant.
| Pattern in the stop records | How to size it | Lever it points to first |
|---|---|---|
| Many stops under two minutes on the same station | Count per shift multiplied by average duration | TPM: minor stops, autonomous maintenance, root cause on the station |
| Long, infrequent stops with maintenance called | Total hours and mean time between failures | TPM: preventive and planned maintenance |
| Changeovers far longer or more variable than the standard | Gap between actual and standard duration, per format | Lean: SMED and standard work |
| Stops waiting for material, operator or quality release | Hours per week by waiting reason | Lean: flow, supply and process organization |
| Same machine, same product, very different results by shift | Gap between best and worst shift in hours | Workforce development and standard work |
| Repetitive manual handling that stops the line while people are elsewhere | Hours of stops tied to missing manpower | Technology: automation or cobots, once the process is stable |
For example, a line where stops under two minutes add up to more time than all breakdowns combined will not get much from a breakdown-focused maintenance plan. The same line could benefit far more from focused work on two or three stations that cause most of the short stops. The reverse is also possible: a stop study can confirm that breakdowns really are the main loss, and then the TPM plan stands on solid ground. In both cases, the decision is made on hours measured, not on the incidents people remember best.
A four-week stop study, step by step
- Pick one representative line. Choose a line that matters for output and runs a typical mix. Avoid starting with the most troubled machine; it biases the conclusion.
- Record every stop automatically. Capture start and end from a machine signal, with no minimum duration. Keep the manual log running in parallel for comparison.
- Keep the reason list short. Eight to twelve reasons that operators can choose in a few seconds. Review the “other” share each week and split it if it grows.
- Compare after two weeks. Put the automatic count and the manual count side by side. The gap is the first finding to share with the team, without blame.
- Rank by hours and by count. A Pareto by total time shows where capacity goes. A Pareto by frequency shows where operators lose their rhythm. Both matter.
- Size each lever. Use the table above to assign hours to TPM, lean, workforce development and technology. Write down the hours, the stations and the shifts concerned.
- Choose, then keep measuring. Pick the lever with the largest sized loss that the team can act on now. The same records become the before and after for the project.
TEEPTRAK was built for this kind of study. A module wired in the electrical cabinet and a sensor at the edge of the line record every stop automatically, with no connection to the PLC. Installation takes about an hour per machine and OEE is available within 48 hours, so a stop study can start in the week it is decided. Across more than 700 plants in over 30 countries, TEEPTRAK customers report on average 30% fewer unplanned stops. TEEPTRAK measures; the choice of strategy and the improvement work stay with your teams and, where you use them, your advisors.
Further reading
- Practical Strategies for Improving Manufacturing Productivity, Doug Hanawalt, Purdue MEP
- The 6 big losses: what your manual log doesn’t see
- TPM and OEE: how Total Productive Maintenance and OEE work together
FAQ
Why don’t operators record short stops? Because restarting the machine is faster than logging the stop, many logs have a minimum duration, and logs completed at the end of the shift rely on memory. Short stops are real losses, but they rarely survive these filters.
How long should a stop study last before choosing a productivity strategy? Usually three to four weeks on a line with a stable product mix, so that all shifts, the main products and several changeovers are covered. Lines with long product campaigns may need more time.
Does automatic stop recording replace the operator’s input? No. The machine signal records when a stop starts and ends; the operator still gives the reason. The difference is that operators no longer decide whether a stop is worth recording.
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