State-based indicator

A state-based indicator is a visual, digital, or data signal that shows the current status of an asset, process, or system by mapping it to a predefined set of states. In industrial and manufacturing environments, these states are typically discrete and mutually exclusive, such as running, idle, setup, maintenance, faulted, or out of service.

State-based indicators can appear as lights on machines, icons or color codes in MES or SCADA dashboards, or status fields in ERP and quality systems. They are used to represent the real-time condition of equipment, production orders, batches, or workflows so that operators, supervisors, and automated logic can respond consistently.

How state-based indicators are defined and used

• Predefined state model: A clear list of allowed states is defined in advance (for example, run, stop, fault, changeover, quality hold). Each indicator must always be in exactly one of these states at a time.
• Deterministic rules: Logic, sensors, or system events determine which state applies. For example, a machine with motor current and cycle signals may be classified as running, while no current but an active alarm is classified as faulted.
• Consistent visualization: Each state is mapped to a consistent visual indicator, such as stack-light colors, HMI icons, or MES status badges, so that users interpret the meaning the same way across the plant.
• Data collection and analytics: State-based indicators are often logged over time to calculate metrics such as OEE, downtime by reason, changeover time, or time on quality hold.

Examples in regulated manufacturing include:

• Equipment status indicators in an MES that show when a line is in production, changeover, cleaning, qualification, or maintenance.
• Batch or work-order status indicators in ERP or MES such as planned, released, in process, on hold, completed, or closed.
• Quality disposition indicators on lots or serial numbers, such as accepted, rejected, under review, or quarantined.

What state-based indicators are not

• They are not continuous measurements like temperature or pressure values, although those measurements can feed the logic that sets a state.
• They are not free-text notes or unstructured comments; they rely on a controlled list of possible states.
• They are not necessarily alarms; an alarm is typically an event, while a state-based indicator reflects a current condition.

Common confusion

• State-based indicator vs. alarm: An alarm usually signals that a threshold has been exceeded and requires attention. A state-based indicator describes the current mode or condition, which might or might not be alarmed.
• State-based indicator vs. KPI: Key performance indicators such as OEE or yield are calculated metrics. State-based indicators are underlying status flags that can be used as inputs for KPI calculations.
• State-based indicator vs. sensor reading: A sensor reading is raw data (for example, 72.5 °C). A state-based indicator classifies a situation derived from one or more readings (for example, within spec, out of spec, in warm-up).

Operational relevance in manufacturing systems

In OT, MES, and ERP environments, state-based indicators help standardize how systems interpret and act on real-time conditions. They are frequently used for:

• Driving workflow transitions, such as preventing material issue to a work order that is in a hold state.
• Triggering quality or maintenance workflows when equipment enters a faulted or out-of-tolerance state.
• Supporting audit trails in regulated industries by recording when and why assets or lots changed state.
• Feeding operations intelligence dashboards that show current line status, bottlenecks, or nonproductive time.