The circuit may be understood with the following points:
The above circuit can be modified by adding a relay stage for controlling a articular stage which may be relevant to the low battery cut of actions.
The above low battery indicator circuit can be even further improved in the following manner for controling both lower and the upper charging thresholds:
Initially keep the 100K preset link disconnected.
Apply a 14.4V source across the shown “12V input” and adjust the 10K preset such that the upper relay just activates, confirm the triggering by subsequently moving the preset to-and-fro. Glue it once fixed.
The LED will respond by switching ON to the fixing of this preset.
Now reconnect the 100K preset feedback link, and reduce the input supply to about 11.2V.
Next, adjust the 100K preset such that the relay just deactivates. Confirm by flipping the preset as above.
Ignore the lower relay as it will switch ON as soon as the input supply is switched ON, so its operation is obvious.
That’s it, the low battery warning circuit is all set now and will accurately respond to the above settings or any different setting that may be preferred and implemented by the particular user.