Low Voltage battery cut off???!!!

[cpaharley2008]

It is best to have the controller as close to the battery as possible and not to put a battery inside your unit, unless it is a sealed AGM battery and then you the issue of 2 different types of batteries which means the stronger battery will be limited to the weaker battery. Also it is way easier and economical to wire 2 x 12v next to one another vs the long run of wire back and forth to each battery. The two batteries need to be wired together not separately.

[dylanear]

Originally Posted by Bob Miller

You may be reading what is called "surface charge". Put a 10 amp load on for 10 minutes and see whats happening when you take the load off.
If the converter is on and charging you should see about 13.2 volts. A charger can only charge if it's voltage is higher than the batteries.

Perhaps, but I'm pretty sure the battery is good, the only reason I thought it was bad was my meter in the trailer was reading below 8V (minimum reading) and and I was getting no power to the lights. If I'm reading a lot higher than 8V at the terminals I think I have a wiring issue. I'll put the battery on the charger today and just make sure it goes fully charged and into maintenance mode.

[dylanear]

Originally Posted by cpaharley2008

It is best to have the controller as close to the battery as possible and not to put a battery inside your unit, unless it is a sealed AGM battery and then you the issue of 2 different types of batteries which means the stronger battery will be limited to the weaker battery. Also it is way easier and economical to wire 2 x 12v next to one another vs the long run of wire back and forth to each battery. The two batteries need to be wired together not separately.

Yeah, I knew it wasn't ideal nor going to be simple if at all workable. I need to get a scale and try to figure out how adding another type 24 to the tongue will affect the weight on the ball. If it's 1:1 than not sure I can afford to add it.

But I'm also thinking, I might replace the battery I have now with an AGM, then I could add another inside. Electrically, some solar charger controllers support two batteries, that might work for charging them both in different locations. The solar charge controller would be inside, about the same wiring distance to both.

I'd love to have the extra capacity, but must keep the tongue weight down for the sake of my receiver. I bent a less well built receiver and don't want to stress test my current one that's held up well so far.

[dylanear]

Sounds like this might work nicely.

Morningstar Corporation » SunSaver Duo

Morningstar’s SunSaver Duo™ is an advanced PWM two battery controller for RV’s, caravans, boats and cottages. Rated for 25 amps at 12 volts DC, this product will charge two separate and isolated batteries at the same time, such as a "house" and an engine battery, based on user selectable priorities. This controller also includes a backlit remote meter which may be mounted in or on a wall, and displays digital and pictorial status information about the solar power system.

[cpaharley2008]

The issue is wiring two batteries in parallel so far apart. You would almost have to wire each one separate and use a switch. You lose a lot of volts/amps over long runs of wire.

[Roy in TO]

[QUOTE=dylanear;315852]But I'm also thinking, I might replace the battery I have now with an AGM, then I could add another inside. /QUOTE]

If you are replacing 2, consider going 6V you will end up with more amp hours for less $. The 6V tend to be more heavy duty.

[dylanear]

Originally Posted by cpaharley2008

The issue is wiring two batteries in parallel so far apart. You would almost have to wire each one separate and use a switch. You lose a lot of volts/amps over long runs of wire.

That charger I linked to does just that. It has two separate charging channels and there are separate settings for each battery. You can control which gets charged first etc.

[dylanear]

[QUOTE=Roy in TO;315891]

Originally Posted by dylanear

But I'm also thinking, I might replace the battery I have now with an AGM, then I could add another inside. /QUOTE]

If you are replacing 2, consider going 6V you will end up with more amp hours for less $. The 6V tend to be more heavy duty.

Two 6V would have to be in series to get 12V, I don't think you'd want two batteries in series 8 feet apart.

But I'll check with the charge controller specs and see if 2 x 6V would work.

[dylanear]

[QUOTE=dylanear;315900]

Originally Posted by Roy in TO

Two 6V would have to be in series to get 12V, I don't think you'd want two batteries in series 8 feet apart.

But I'll check with the charge controller specs and see if 2 x 6V would work.

Seems the Morningstar Duo (which I just ordered) will do two SETS of batteries, each set could be a pair of 6V I suppose.

[Bob Miller]

As long as we are spending your money; if you get two 6 volt batteries, get Golf Cart batteries, they are designed for more abuse and discharge/recharge cycles than starting or marine type batteries.

[dylanear]

Originally Posted by Bob Miller

As long as we are spending your money; if you get two 6 volt batteries, get Golf Cart batteries, they are designed for more abuse and discharge/recharge cycles than starting or marine type batteries.

Not sure what batteries I'll end up with at this point, but was thinking lately of two type 31 120ish amp hour AGM deep cycles. Only 20 lbs more on the tongue, but lot's more amp hours compared to the 80ah on my current grp 24 flooded. I'll look at the 6Vs and compare at some point. The AGM seem like the thing for me. I know I'll never take proper care of flooded batteries over the long haul, and perhaps more importantly, I want to put one battery in the cabin, so AGM is a requirement there. Not the cheapest option, but I kill batteries dead by blinking, so I may even come out ahead in the long run with the more durable glass mat tech.