[Nut-upsuser] Setting up charge/voltage based shutdowns

[Roger Price]

On Sun, 6 Aug 2023, Jim Klimov via Nut-upsdev wrote:

>   While looking at https://github.com/networkupstools/nut/issues/2014 I understood that I am
> not sure if currently NUT has a standard way of triggering a shutdown based on remaining charge
> or runtime, if a device/driver lacks a `battery.charge.low` setting but has readings for the values
> themselves.

My personal choice is to shut down after a some time, in my case 2 minutes.  How 
much of the battery charge this consumes is a matter for the initial 
configuration of the setup.  The "shutting down now" message says how much 
charge is left.

However I have the impression that this strategy is not popular.

In the case of repeated wall power failures, the shutdown when battery charge 
drops to x% doesn't work.   Better would be shutdown when battery drops BY y%.

Roger