Need a new battery monitor?

[guntertl]

Hi there, we own a 2010 19ft Flying Cloud and full-timed in it last Spring-Fall for 6 months. We are looking to do the same again this summer and are planning to upgrade our power system. We already own a CEA Solar 80AMP Portable Solar Panel (has a built in charge controller) and have been quite happy with it.

Here is the plan so far:

1. Change out the OEM Parallax converter (one stage) with a IOTA Converter Model DL-55IQ4 (three stage) converter
2. Change out our Interstate 12V Batteries (already trashed after one year) with 6V Lifelines GPL-4CT in series. This will require raising the box height as has been mentioned in several threads.

I know none of this is new but the question we have is around the effectiveness of the OEM battery monitor. We've been reading about "surface charges" being misleading and want to make sure we have an accurate read so we don't take the batteries below 50%. We put a Xantrex monitor in our old camper van but I felt like it was a bit overkill. Don't need to count electrons or anything:0) Being able to read voltage draws and amp hours is nice though.

So, is the stock model with it's little lights and such sufficiently accurate or should we upgrade to protect our investment. If so; recommendations on good monitors?

Thanks in advance.

Tod and Lisa

[barts]

I really like the TriMetric battery monitor; it is easy to use and integrates current over time to give an accurate idea of the state of charge. I'm sure there are fine monitors; I know this one works well. No connection except satisfied customer of both Trimetric and Bestconverter.com

- Bart

[bryanl]

re: "80AMP Portable Solar Panel" -- you mean 80 watt?

Battery capacity is a matter of weight although AGM batteries tend to be on the low capacity end of the curve. Generally, wet cells tend to be most cost effective and whether you use 6v or 12v is of no matter. It is total battery bank weight that counts.

As for monitoring the battery, voltage will tell you state of charge. As with any measure, it must be done properly and properly interpreted. Generally, don't let the voltage go below 12.2v as measured after no significant charge or discharge for at least a half hour.

re: "integrates current over time to give an accurate idea of the state of charge." -- As for the electron counters - they are a lot of fun but do be aware that they must be properly programmed and even then don't measure the influence of such things as age, cycle to cycle variations, and other significant factors. (temperature, usually, use profile, somewhat).

An 80 watt panel is minimal for 80 pounds of battery (like 2 group 24's). Plan on about 2 hours at peak output for your solar energy harvest per day which would be 160 watt hours for that panel. Keep in mind that the typical residual load in the trailer is about 10 watts which is about 240 watt hours per day.

so much hype ... so little time! ;-)

[idroba]

I like my simple, but very accurate ammeter to show what is going into and out of my batteries.

http://www.airforums.com/forums/f449...tem-88434.html

[guntertl]

Thanks for the suggestions. I assume from the replies that many folks do some level of their own monitoring, rather than relying on the Stock version. I am likely not vigilant enough to do my own measuring "by hand" so will investigate the monitors suggested. Oh, and yes, I did mean watts on the solar panel!
Thanks again!