The message could come from multiple places, but in general it means that the TCP connection to your modbus equipment was closed, and not by Mango. When you are using the keep-alive, Mango detects the condition and attempts a re-connect upon the next polling. If the stream was closed during a poll, the remainder of the poll will fail. Overall it indicates network problems.

Hi CAHA,

It's a two step process (assuming you have Mango already pulling data from your sensor). Edit the point by adding a point event detector (either a high limit, a low limit, or both in your case), and save. Then, head over to the event handlers page and add an email handlers to your event(s). That's it.

The division between events and handlers allows 1) events to generated in arbitrary ways, and 2) events to be handled in multiple ways.