Menu
Why Is My OEE Low? A Troubleshooting Guide

Why Is My OEE Low? A Troubleshooting Guide

A low OEE always traces to one of three losses. Here is how to split it, find which loss is bleeding, and fix the biggest leak first instead of guessing.
Why Is My OEE Low? A Troubleshooting Guide

Key takeaways

  • A low OEE is always caused by one of three things: availability, performance, or quality loss.
  • Do not try to fix OEE directly. Split it into the three factors and find which one is dragging it down.
  • Then find the single biggest cause inside that factor, and fix that first.
  • Averaging OEE across lines or shifts hides the real problem, so always diagnose at the machine level.

"Why is my OEE low" is the wrong question to act on directly, because OEE is a product of three separate numbers. A 55 percent score tells you there is a problem, not where it is. The fix is to stop staring at the headline number and break it apart.

Start by splitting OEE into three

OEE is Availability times Performance times Quality. A low score means at least one of those three is low. Before changing anything on the floor, look at all three and rank them. The lowest one is where your loss lives, and it is almost never spread evenly. See how OEE is calculated if you need the formula first.

If availability is the low one

Availability loss means the machine is not running when it should be. The usual causes:

  • Breakdowns and unplanned stops.
  • Long or frequent changeovers.
  • Waiting on materials, operators, or upstream lines.

Symptom: the machine sits idle or stopped for long stretches. If availability is your lowest factor, downtime is the fight, and reason-coded stop data is where to look first.

If performance is the low one

Performance loss means the machine runs, but slower than it should. This is the sneakiest loss because the line looks busy.

  • Micro-stops: brief stoppages that never get logged.
  • Reduced speed: running below the ideal cycle time.
  • Small jams, misfeeds, and hesitations.

Symptom: the machine is running most of the time but the count is short. It helps to be clear on availability loss versus performance loss, because teams often blame downtime for what is actually a speed problem.

If quality is the low one

Quality loss means the machine makes product you cannot sell.

  • Scrap and rework.
  • Startup and changeover rejects.
  • Out-of-spec output that has to be scrapped or reprocessed.

Symptom: good units are well below total units produced. Quality loss is usually concentrated at startups or after changeovers, so that is the first place to look.

Find the biggest single cause

Once you know the dominant factor, do not fix the whole category. Within it, one or two causes usually account for most of the loss. A quick Pareto analysis on the reason-coded data points straight at them. Fixing the top cause of the top loss moves the number far more than spreading effort across everything.

The mistake that hides everything

The most common reason OEE stays low is that it is averaged. A plant-level or shift-level average blends a healthy line with a broken one and shows a mediocre middle, so nobody knows where to act. Always diagnose at the machine and the loss level. When the data is live and reason-coded rather than averaged in a spreadsheet, the biggest leak is obvious. That is what Fabrico is built to show. See the approach on a connected OEE platform, then work through how to improve OEE once you know the target, or book a demo.

Frequently asked questions

What is a low OEE?

It is relative to your line type, but the useful move is not to judge the headline number. Split it into availability, performance, and quality and see which factor is dragging it down.

Which loss should I fix first?

The lowest of the three factors, and within it the single biggest cause. Chasing a small loss while a big one bleeds is the usual waste.

Why does my OEE look fine but output is short?

Usually performance loss: micro-stops and reduced speed. The machine runs, so it looks healthy, but the count falls behind the ideal cycle time.

Can bad data make OEE look low?

Yes. Manual logging misses micro-stops and mislabels stops, which distorts the split. Automatic, reason-coded capture is the fix.

Why does averaging hurt?

An average blends good and bad machines into a meaningless middle. Diagnose per machine and per loss, never at the plant average.

Dernières nouvelles de notre blog

Définissez votre feuille de route en matière de fiabilité
Validez votre retour sur investissement potentiel : réservez une démonstration en direct
Définissez votre feuille de route en matière de fiabilité
En cliquant sur le bouton Accepter, vous donnez votre consentement à l'utilisation de cookies lors de l'accès à ce site Web et de l'utilisation de nos services. Pour en savoir plus pour en savoir plus sur la manière dont les cookies sont utilisés et gérés, veuillez consulter notre Politique de confidentialité et Déclaration relative aux cookies