Charger Charge Rate Settings

[billdean]

Those of you that are using an inverter/charger like a Magnum MMS1012 with 2 Trojan t-105 batteries what Charge Rate setting do you use? The above charger is a 50 amp charger. When dry camping with a generator I would think you would want to set the charge rate as high as you can so you can charge your batteries back without running your generator for 3 or 4 hours or more. I see Trojan recommends 10 to 13% of the 20hr Capacity, which would be 25 to 30 amps at the Bulk stage. Just wondering what everyone else does and how its working for you? 

[Devilishjim]

A quicker charge is hard on batteries and would really throw some heat to them. A lot of car chargers will put out 100amp but sure dont want to charge at that rate.

[lenp]

My MH has three Trojan T1275 (12 volt/450 Amphrs) batteries.  The stock Heart 2000 watt inverter/charger pushed 90-100 amps into the battery bank when when I first start the generator (when batteries are below 75%) and slowly tapers off over the first hour.  At that point (if I am in the trees with limited solar) I am usually around 90% and call it good then let the solar top them up.  If out in full sun I just let the solar do it's thing (750 watts).

Lenp

[mptjelgin]

A maximum charge rate of C/5 is often recommended for flooded lead acid batteries.  That would give you 45 amps as a max charge rate. You will find that the charge will begin to taper off pretty quickly at that rate, as it won't take long to climb to the maximum bulk rate voltage.

I have 4 T-105 batteries and my Magnum 2012 is set for a 100 amp max. I seldom see it hit over about 85 amps, and it doesn't stay there for long. But I don't let my batteries get deeply discharged and I'm sure that plays a role. I wouldn't hesitate to set your charge rate at 40 or 50 amps.