Glossary · System coordination, integration and orchestration
Heartbeat monitoring
Also known as: keep-alive monitoring, life-sign monitoring
German: Heartbeat-Überwachung
In automation and distributed systems, heartbeat monitoring is the supervision of a partner's heartbeat signal, in which the absence of an expected heartbeat within a defined time is treated as a failure of the partner or of the communication path and triggers a defined reaction.
- System integration
In one sentence
Heartbeat monitoring treats a missing heartbeat within a set time as a partner or communication failure and triggers a defined reaction.
Example
When the cell PLC misses three heartbeats from the robot controller, it stops the infeed and shows “Robot communication lost” on the HMI.
How it applies
- Engineering: Define the detection time, the reaction (stop, hold, degrade, fail over) and how the monitoring recovers when heartbeats resume. Automatic resumption after a communication loss must not start motion unexpectedly.
- Safety: Standard heartbeat monitoring is a diagnostic function. Where loss of communication could lead to a hazard, safety-related communication with its own monitoring, such as a safety protocol with watchdog time, is needed.
- Documentation: Document detection times and reactions in the interface specification. Manuals should explain the resulting messages and how to restart safely after communication has been restored.
Heartbeat monitoring vs. timeout
A Timeout supervises one expected response, for example an acknowledgment. Heartbeat monitoring supervises continuous liveness, independent of any particular request.