Mitsubishi Electric MELSEC iQ-F Series User Manual page 15

Terms
Topic
Will
Description
A key to be used for messaging
In the topic hierarchy, a slash (/) is regarded as a delimiter. For example, when multiple sensors send their
individual information to the topic, the messages can be appropriately organized according to their
installation location and device name.
This function sends a Will message with a specified Will topic name to subscribers when the publisher is
disconnected and the server communications are disabled.
If any unexpected disconnection or such an event occurs, subscribers can judge that the publisher is
disconnected.
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