Signals & Alarms
Overview
Section titled “Overview”Signals connect the visible twin to machine state. In a standalone model, simulated sensors, drives and logic provide the values. In Live mode, an industrial interface or realvirtual CONNECT discovers PLC signals and exchanges values with the running machine.
realvirtual WEB presents signal values in the hierarchy, component information, CONNECT panel and signal search. A delivered HMI can also combine those values with configured status indicators, alarm messages, KPIs and documentation.
PLC signal convention
Section titled “PLC signal convention”realvirtual uses Boolean, integer and floating-point signals with an explicit direction. The direction follows the PLC convention:
| Signal | Meaning in realvirtual WEB | Typical use |
|---|---|---|
| PLCInputBool / Int / Float | The PLC writes the value and the viewer reads it | Sensor state, drive position or counter |
| PLCOutputBool / Int / Float | The viewer writes the value and the PLC reads it | HMI command, setpoint or program selection |
The displayed signal name comes from the model or the connected controller. A signal can also retain its full hierarchy path so the twin can resolve the correct component when names repeat.
Signal display and connection status
Section titled “Signal display and connection status”- A signal chip can show its name, direction, type and current value, depending on the selected display level.
- Hovering a chip can reveal the full signal details, source and component bindings.
- For an active Boolean value, green identifies a PLCOutput and red identifies a PLCInput. These colors describe signal direction, not connection state.
- An inactive or otherwise non-active value is grey. An amber force marker identifies a signal whose value is currently forced or overridden.
- Connection and binding information is shown separately where the active workspace provides it. A lost connection can reconnect automatically when that option is enabled; confirm that Live mode is connected before acting on a displayed value.
Alarms and machine status
Section titled “Alarms and machine status”Alarm and status presentation is configured with the delivered twin. Supported HMI content includes alarm dashboards, messages, drive and sensor states, KPI overlays and production charts. A configured alarm can provide operator guidance or open the associated diagnosis and documentation workflow. Do not assume that every standalone GLB contains an alarm list or live data connection.
Quick Start
Section titled “Quick Start”- Open the twin in its HMI workspace and identify whether it is running in standalone or Live mode.
- Select a component and inspect its signal chips or status indicators.
- Hover a signal chip to review its name, direction, type, source and current value.
- In Live mode, confirm that the connection and binding status indicate live data before acting on a value.
- If the twin provides alarms or messages, open the relevant entry and follow the supplied component, document or diagnosis context.