Digital Andon vs. Andon Lights: What Your Plant Actually Needs

Andon comes from the Toyota Production System. The idea is simple: when something is wrong, anyone on the line can signal for help immediately, and that signal is hard to ignore. Traditionally that meant a pull cord or button that lit a light or a board above the line.

The idea is as good as ever. What has changed is how a plant can put it into practice.

The traditional approach: lights and cords

A hardware Andon system usually means stack lights or a display board, buttons or cords at each station, and wiring between them. Some connect to a PLC or a central controller.

What it does well: the signal is physical and obvious. Everyone in the area sees the light. On a high-volume line where seconds matter, that immediacy is hard to beat.

What it asks of you: hardware, installation, and often an electrician or controls integrator. Changes mean rewiring or reprogramming. And a light tells you that something is wrong at a station, but usually not what kind of help is needed, who is responding, or how long it took, unless you add a data layer on top.

The digital approach: requests on screens you already have

A digital Andon system moves the signal onto phones, tablets, and TVs. An operator taps the kind of help they need, the request appears on a board, someone claims it, and the system records the timing.

What it does well: it says what is needed, not just that something is wrong. It shows who owns the request. It captures response and completion times automatically. Adding a new request type or work area is a settings change, not a wiring job.

What it asks of you: devices on the floor, a reliable Wi-Fi signal, and a few habits, mainly that people tap the request instead of yelling for help, and that responders claim what they take.

Questions that tell you which fits your plant

How many stations need to call for help? A few fixed workstations on a high-speed line lean toward hardware. Many areas with varied needs, like material, maintenance, quality, or a supervisor, lean toward digital.

Do you need to know what kind of help, or just that help is needed? If the right responder depends on the type of problem, a light alone won't tell you.

Do you need the data? If you want to bring response times to your improvement meetings, the system has to record them. Hardware can do this, but usually as an added project.

What are your budget and timeline? A digital system can usually be set up in days on existing devices. A hardware project involves purchasing, installation, and integration.

Who will maintain it? If there's no controls engineer on staff, a system you can change from a settings screen will stay accurate longer.

You don't have to choose forever

Some plants run both: lights on a critical line, digital requests everywhere else. The point of Andon isn't the technology. It's making problems visible fast and making sure someone owns the response.

If you're working out what slow response costs you today, the free calculator at andontool.com/downtime-cost-calculator is a good place to start. For a quick intro to Andon Tool, there's a short video at andontool.com/demo.