I added one of these Voltminders. It has an alarm that can be set as well. You can keep an eye on your convertor and the battery when the there is no shore power attached.
This post has the convertor upgrade and it has a link to the Voltminder and where I bought it. Power Convertor Upgrade
If you have a digital volt meter, yes you can use this too.
For what volts are what charge percent, see this web site. The 12 volt side of life part 1
It also has a lot of other good info in it.
And see this part 2, The 12 volt side of life part 2
It talks about invertors which you asked on in your other post.
Good luck and hope this helps.
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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