Battery Question

First of all, the solar controller is NOT a cheep one stage controller! It is a Viewstar 30A programmable 3 stage controller. Nor is the converter for that matter! I'm going to take Boon Docker's advice on this and not worry for now. I will be switching out batteries this week to 4 Trogan T-105's and will go from there,

14.4 in the evening doesn't meet the definition of "fine" in my books :)

Daddy Bear, just do as you have been doing. Everything is working fine.

corvettekent wrote:
Just unplug your converter and let the solar charge the batteries.

If controller is a 3-stage, yes. Though leaving converter on wouldn't hurt either.

If it's not a 3-stage, - unplug the controller couple hours after it's reached 14.x and leave the converter on.

The key is getting battery to 14.x and then floating at 13.x.

Just unplug your converter and let the solar charge the batteries.

Not so fast.

14.x is Absorption stage. 3-stage controller would stay there for a while and then drop to Float 13.x.

When it's cloudy it will get to 14 only by the evening, so this is what you will see then.

Some low end controllers are one-stage, i.e. it will be stuck at 14.x until sun goes down or until you manually change it to 13.x (recommended).

In the morning controller starts from scratch again, raising voltage to 14.x and then dropping to 13.x (or not dropping), but it's always trying to raise it first.

Now, - converter...

"IF" converter also has Abs stage, then at sunset you could observe 14.x from either controller or converter or both.

If converter has no Abs stage, but it's cloudy and battery was low in the morning (or controller is a one-stage set to 14.x), then at sunset you would observe 14.x Abs stage of controller.

So... Assuming older model of converter that has only one stage - Float 13.x, - everything is fine except for controller :).
It is either not getting enough sun to get through the Abs stage, or it is a low-end one-stage, or the Float is set too high.

Thanks guys, that makes more sense now.

Papa Bear

14.4v is the absorption cycle of the converter, when it is pumping amperage into the battery. 13.3v is the float cycle of the converter, when it is maintaining the charge. Everything sounds like it is working as intended.

you don't want your charger to hold 14+ volts all the time, that'll boil your batteries. sounds like you have your charging system setup just fine. 13.3 sounds like the float voltage your shore-powered converter is set at.