SMTP without authorization, different text mail

[borgmcz]

Now, if you have LOW state, on end mail you have 0 and HIGH state you have 1

This is not user friendly.

A better choice would be the possibility of a separate state for the text as HIGH as a separate text for state LOW.
You will get the opportunity to understand messages such as these:

Work on the battery
Working from the AC network
......
pump works
pump off
.....
operation OK
battery fault

You can obtain a clear message to the user.