Battery charging via inverter/charger

[RayIN]

Much is made of 3-stage battery charging, some inverter/chargers even have 4-stage charging. From reading various posts, I thought this was standard practice.
I just installed a new Xantrex SW 3012 inverter/charger. While reading through the 124 page owners manual, this stood out;
Quote:
"Two-Stage Charging Process
Two-stage (or no float) mode differs from an ordinary three-stage charge
mode in that it does not continuously maintain the battery at float voltage.
Instead, the Freedom SW begins charging the battery in bulk mode
whenever the battery voltage drops below the recharge level. While the
battery voltage is above the recharge level the inverter’s AC transfer switch
continues to pass power through from the utility grid to the loads, but does
not actively charge the batteries.
Two-stage mode increases efficiency of utility connected systems by
reducing the amount of power consumed by the inverter and batteries
compared to when the battery is continuously maintained at Float
Voltage. This feature can extend the life of most batteries."


reference: https://www.invertersupply.com/media...wnersGuide.pdf

 

[John From Detroit]

There are several that do that.

Many batteries have a significant "leakage" so you need that float to keep 'em charged up... (Very slight charge current) or like Progressive Dynamics does it kick up to Boost level for a few minutes about once a day. (Best practice for LA batteries I think)

Some of the newer Batteries (LiFePO4 for example) You can let 'em sit a year and they still read 100% or at least 95

 

[Gary RV_Wizard]

I've never heard that float charging was less than ideal for battery life. Or that it used a noticeable amount of shore power, though obviously there is some.
Two stage charging sounds ideal for LiFe batteries, though.

 

[Mark_K5LXP]

Sounds like a way to turn a cost reduction into a feature. Float charging takes literally a handful of watts.

Mark B.
Albuquerque, NM

 

[RayIN]

Sounds like a way to turn a cost reduction into a feature. Float charging takes literally a handful of watts.

Mark B.
Albuquerque, NM

Mark, Xantrex iverter//chargers have both 3 and 2 stage charging profiles. My 20 yr old Xantrex RS2000 has both charging profiles. They can't be saving money on anything.
That means they have the data to back up their statement, or they'd be saving money by eliminating the 2 stage profile.
Ya, I know, us old dogs change hard.

 

[Go Go Gadget]

Some good information, new to the forum hope to lean more.