What is the Andon system
The Andon system is a visual alert system used in factories to detect and communicate production incidents in real time.
Through signals such as Andon lights, signal towers, Andon boards or digital alerts, operators can immediately report problems on a production line, such as machine failures, quality defects or lack of materials.
This system is part of the visual management tools used in Lean Manufacturing plants and allows teams to react quickly to any anomaly in the production process.
The concept originated in Japan within the Toyota Production System, where it was used so operators could stop the assembly line whenever they detected a defect or abnormal situation.
Today, this type of solution is used across multiple industrial sectors and is often integrated with production monitoring tools and MES systems, enabling real-time data about the status of the factory.
Types of Andon systems
There are different ways to implement an Andon system depending on the level of digitalization of the manufacturing plant.
- Manual Andon: the operator activates a signal using a button or pull cord when a problem is detected.
- Light-based Andon: uses signal towers or visible panels to indicate the status of a machine or workstation.
- Digital Andon: integrates with MES software or monitoring systems to generate automatic alerts based on production data.
- Automatic Andon: alerts are generated automatically when the system detects anomalies such as machine stops or process deviations.
How an Andon alert system works
An Andon system works as a production alert system that makes incidents visible in real time within the industrial plant.
When an operator detects an anomaly — such as a quality defect, machine stoppage or lack of materials — they can activate an Andon signal from their workstation.
This signal is displayed through Andon lights, signal towers or Andon boards, allowing supervisors and technicians to quickly identify where the problem occurred and preventing incidents from spreading along the production process.
| Color | Meaning |
|---|---|
| Green | Production running normally |
| Yellow | Warning or minor incident |
| Red | Stop or critical issue |
| Blue | Request for assistance |
| White | Material shortage |
What Andon is used for in an industrial plant
The purpose of Andon is to improve the visibility of production status and accelerate problem resolution.
In a factory, it can be used to:
- Detect anomalies at a workstation.
- Alert about machine failures.
- Signal quality issues.
- Notify material shortages.
- Communicate incidents to supervisors or maintenance technicians.
Thanks to this approach, companies can reduce defects, improve team coordination and maintain a more stable production flow.
Relationship between Andon and Lean Manufacturing
Andon is deeply connected to the principles of Lean Manufacturing, a methodology focused on maximizing customer value by eliminating waste in production processes.
Within this approach, the visual alert system allows companies to:
- Detect problems as soon as they occur.
- Stop production to prevent serial defects.
- Improve transparency regarding factory status.
- Encourage a culture of continuous improvement or Kaizen.
This type of tool helps create more efficient and controlled industrial processes.
Main benefits of the Andon system in industry
Immediate identification of incidents
Problems are detected at the exact moment they occur, enabling a rapid response from supervisors or technicians.
Reduced downtime
Faster problem resolution reduces unplanned downtime.
Continuous process improvement
Incident records allow companies to analyze patterns and implement improvements to prevent recurring issues.
Better quality control
The possibility of stopping the line when a defect appears prevents defective products from being produced in series.
Improved communication on the shop floor
Visual signals facilitate coordination between operators, supervisors and maintenance teams.
Example of use in a production line
In an industrial assembly line, an operator detects that a component has a defect.
The typical process would be:
- The operator activates the Andon alert from their workstation.
- The signal tower changes color to indicate an incident.
- The supervisor or maintenance team receives the alert.
- The cause of the problem is analyzed and corrected before continuing production.
This procedure prevents defective products from advancing along the manufacturing line.
How to implement Andon in a factory
To implement this alert system in an industrial plant, several steps are recommended.
Define visual signals
It is necessary to establish which colors or alerts will be used and what each one means.
Train personnel
Operators must understand when to activate the system and how to respond to incidents.
Connect the system with digital tools
Integration with monitoring platforms allows events to be recorded, data to be analyzed and production traceability to be improved.
Integration with MES systems and factory digitalization
In many factories, Andon solutions are integrated with MES systems such as Mapex to obtain a more complete view of the production process.
This integration allows companies to:
- Visualize the status of production lines in real time.
- Generate automatic alerts when incidents occur.
- Record production events.
- Analyze downtime and bottlenecks.
By combining visual signaling with operational data, companies can optimize production management and improve plant efficiency.
The Mapex MES platform provides the necessary tools to configure various visual signals or alarms that deliver real-time information about the status of production lines.
Additionally, our MES solution can communicate with acoustic and visual signal beacons from different manufacturers, allowing colors and states to be customized according to each company’s needs.
FAQs about the Andon system
What is an Andon tower?
An Andon tower is a light device used in factories to display the status of a machine or workstation using different colors.
What is an Andon board?
An Andon board is a screen or visual board that shows the status of production lines and active incidents within the plant.
What is an Andon light?
An Andon light is an industrial signal tower that shows the status of a workstation or production line through different colors.
What is the difference between Andon and other visual management systems?
Andon is specifically designed to notify incidents in real time, while other visual management systems display performance indicators, production metrics or planning information.
What does Andon mean in Japanese?
The word Andon means lantern or paper lamp in Japanese. In the industrial context, it is used as a metaphor for a visual system that alerts about problems in production.
Where did this system originate?
The system became popular within the Toyota Production System (TPS) developed between 1948 and 1975 by Taiichi Ohno, Eiji Toyoda and Shigeo Shingo.
