Downtime Reason Codes at the Ignition HMI

Published 22 October 2026 · 5 minute read

Downtime reason codes are only as good as the moment they are entered. Ask an operator an hour later and the answer is "other". Ask at the HMI while the machine is stopped and you get the real reason.

Why the HMI is the right place

• Context. The operator is standing at the machine and knows what happened.
• Timing. The stop is detected from the PLC; the prompt appears once it passes a threshold such as two minutes, so short blips do not interrupt anyone.
• No second login. The reason is recorded as the operator signed in at the HMI.

What a good downtime prompt does

1. Category first, then the code. Mechanical, electrical, material, quality, changeover: two taps, not a sixty-line list.
2. An optional comment for what the code cannot say.
3. Earlier stops still open listed below the current one, so nothing slips through a shift change.
4. Never asks twice. Once a stop has a reason, from this HMI or anywhere else, the prompt does not come back, not even after a gateway restart.
5. Works offline. A code entered while the network is down waits in a queue and is sent when it returns.

From codes to decisions

Reason codes feed the downtime Pareto and the availability part of OEE. With every stop coded at the line, the Pareto shows the real top losses per machine and shift, instead of an "uncoded" bar that hides them. See how to track manufacturing downtime for the categories and the cost side.

The PulseMQ MES Connector for Ignition adds this prompt to any Perspective HMI: a Downtime button on the Station bar that turns red when a stop needs a reason.

Get every stop coded →

Frequently asked

When should the operator be asked for a downtime reason?
While the machine is stopped, once the stop passes a short threshold such as two minutes. Asking later produces vague reasons, and asking for every short blip interrupts the operator for nothing.

What happens to a stop nobody coded?
It stays in the list of earlier stops without a reason, so the next operator or the shift lead can code it.

How do reason codes improve OEE?
They show where availability is lost. A downtime Pareto built from coded stops shows the real top losses per machine and shift.

Ignition is a trademark of Inductive Automation. PulseMQ is not affiliated with or endorsed by Inductive Automation.