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ron_dittmer's avatar
ron_dittmer
Explorer II
Oct 13, 2014

Batteries: Two-6V In Series, or Two-12V In Parallel ???

Before spring I will be replacing our two 12V Walmart coach batteries. Our 7 year old rig has it's original Tripplite 2000 watt inverter/charger similar to THIS ONE. I was thinking of replacing the ...
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DiploStrat's avatar
DiploStrat
Explorer
Oct 24, 2015
pnichols wrote:
… No matter what the source, whenever the coach's 12V system voltmeter indicates that voltages greater than about 12.8 volts are present and the ammeter indicates coach battery current is zero or only slightly positive ... then the coach batteries are fully charged. This is a very simple and full-proof battery condition monitoring method that has worked well for us for years on AGM coach batteries.


With the addition of the ammeter, I agree completely.

But, as noted, a voltmeter alone will not give a great state of charge in an active system. It is fine for a resting battery, but batteries installed in an RV are rarely, if ever, at rest.

An hour counter is useful in giving you an estimate of how far down you are and how much longer your charge will take. (But even this is only a guestimate depending on the algorithms your meter uses.) An hour counter is also useful in assessing the impact of a given appliance, like a microwave.

At the end of the day, the most important thing is that your charger(s) have a reasonable profile and that you charge your batteries fully and often.

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