I have some RB333 that I see have voltage monitoring. I’m planning to upgrade one site to an RB600A. Looking at the docs, it would appear that the 600 lacks the voltage monitoring feature. Is that the case ? If so, what’s the best option for adding a simple voltage monitor (this is a solar site, so I need some kind of remote voltage monitor). Previously we used an ethernet temp/voltage sensor, but I’d prefer to use something lower-power, since the RB600 + radios will use most of the site’s power budget.