Flexible Solar Panel - Will This Wire Cause Problems

OP HERE...

This is what you guys are talking about, right? I found this in an article online:

The voltages at which the controller changes the charge rate are called set points. When determining the ideal set points, there is some compromise between charging quickly before the sun goes down, and mildly overcharging the battery. The determination of set points depends on the anticipated patterns of usage, the type of battery, and to some extent, the experience and philosophy of the system designer or operator. Some controllers have adjustable set points, while others do not.


Here's the complete article, if any other new solar guru-wannabees are interested:

An Introduction to Charge Controllers

It's working
See if you can set "load" to Off

Right now it's set to run 24 hrs and only shut off if battery voltage hours below 10.7

By turning load off, there will be no power on the load terminal screws
Makes for an additional safety factor, one less thing to accidentally go wrong

Hi Mitch,

It is unlikely to fry the battery unless you have quite a few watts and a relatively tiny battery bank. The limit is about 15 to 20 watts per 100 amp-hours without a controller.

Once you have finished "tweaking" the controller it will be "set" and you can "forget" it.

mitch5252 wrote:

It was my understanding that hooking the solar panel directly to the battery would "fry" the battery, and that having a solar controller would be more like my 3-stage trailer converter thing - just pump in juice as needed, without "frying" the battery.

What have I missed?...I sure don't want to have to babysit this thing. I honestly thought it would be plug 'n go.

Thanks for your replies.

Different controllers, different "charging profiles" Some have two adjustable voltages, one for what it gets the batteries up to and then another for Float what it does after that.

That one will not need baby-sitting once you get used to it and have the voltage set right for your situation where camping. When your situation changes you can adjust the voltage and be good again for that time there.

If you have the battery capacity and the panel amps so that the battery takes all day to reach the voltage setting, there is nothing for you to do anyway. If you had a big array and a small battery you would get to 14.x real soon in the day and then you would have to go out and change the voltage setting to a lower number. Some controllers have a selectable voltage for that and drop to that by themselves.

The one you have is more of a load controller for being able to run loads with out draining the battery right down (it will shut off the load if the battery gets to your selected low voltage for that and turn the load back on when the battery is recharged some.) as well as being able to charge up the battery

For a three- stage charging profile but with no selectable voltages you could get a LandStar 2020 which might do for you. (no ammeter though--yours has that) It gets the batts to 14.6, stays at 14.6 for two hours, and then drops to 13.8 all by itself. This suits many situations. No operator required.

You also need to match to battery type. Some charging profiles and voltage settings are good for Wets but not for some AGMs but ok for other AGMs. Selectable voltage like on yours is good for that.

IMO live with it for a while and see if it suits you. If not, by then you will know better what you want in your next controller. Or ask on here. Each poster will say to get the same as what he has because it is the best. :)

OP HERE - another case of confusion...

I thought this solar charge controller (both the PWM and MPPT types) were more or less like a 3-stage converter in my trailer. My first trailer had a single stage converter and just happily bubbled away at full throttle, doing damage to the battery. I replaced it with a 3-stage controller for better battery life. Now, my new trailer has a factory installed 3-stage converter.

It was my understanding that hooking the solar panel directly to the battery would "fry" the battery, and that having a solar controller would be more like my 3-stage trailer converter thing - just pump in juice as needed, without "frying" the battery.

What have I missed?...I sure don't want to have to babysit this thing. I honestly thought it would be plug 'n go.

Thanks for your replies.

greenrvgreen wrote:
BFL, what does "Controller PWM 13.7v" mean? Would this have something to do with Float?

Also, it's not the heat, it's the humidity.

That is the actual voltage (be same at panel as at battery) It is on a full battery but with a 40w load so it is doing 3.x amps (divide by 10 rule) to run that load

At the moment the Vabs is set at 13.8 and batt is there except for that load to 13.7. Float and Vabs are the same thing with this controller (same as my Solar30--seems to be made by the same company or to some same standard display method)

You will have to be on top of things so you can decide how to operate that controller for your situation. You don't want to get to 14.8v mid-morning and leave it there all day while the battery bubbles away too much of its water. That controller voltage is temp comp but your battery is not. :) So in really hot weather that 14.8 might be too high. (watch the battery water level-don't forget-get an idea how long it takes to get down to need a refill)

OTOH if you start the morning with the battery low and you don't get to 14.8 until late afternoon that is perfect, because you want some time at that 14.8 to finish charging the battery.

Some cloudy days might be good for that and some sunny all day days might not be so good where it gets to 14.8 too early for you. How the heck can you know what is good and not like that? Watch your battery water levels closely. You will lose some but should not be losing a lot.

It is not a fire and forget gizmo. It needs you to keep an eye on things and adjust the voltage as conditions change over the days, locations, and seasons. Just more chores to do!

BFL, what does "Controller PWM 13.7v" mean? Would this have something to do with Float?

Also, it's not the heat, it's the humidity.

BFL13 wrote:
The 34C means I am glad I am not there! :)

YAY - HE SAYS IT WORKS!! I'll go change that voltage.

I tried to find a button to switch between Centigrade and Fahrenheit - no go. Yes, you are glad you are not here - I'd be picking your brain until it hurt!!! :)

Ok it works :) Now use the setting buttons to set that "PV OFF" figure to say 14.8v. That is the "ceasing charging" voltage the battery will then reach before the controller starts "controlling" ie, stops the voltage from getting any higher.

AFAIK that will also be your chosen Float voltage, so reduce that to say 13.2v if your batts are full and you are not using the trailer for a few days.

The 34C means I am glad I am not there! :) BTW keep the controller in the shade, where it can't get rained on either, not sitting out in the sun when installed.