12 hours of unbroken sunshine for 3 hours of light can't be right....

pebbleclur · February 2014

I have 4 x 12 v deep cycle solar batteries attached parallel (?) to run my 12v lighting and an inverter for fans and charging of phones/computers.
Attached is how it was set up historically by my ex and I want to know what I can do to improve it

Attachment not found.

Questions:
Should the cables from the inverter and solar charge controller (Morningstar ProStar 30) come from just the first battery or should the +ve come from battery number 1 and the –ve from number 4?
My inverter goes straight to the battery and does not touch the charge controller. I think this is the reason why, when the charge is down, the lights go off but my fan will still work for a time afterwards (until the invertor starts beeping that the power is drained!). How can I make sure that the lights stay on longer than the invertor?
Charge Controller – on the ProStar 30, there’s an option to select Gel, sealed or flooded. I was told it should always point to Gel even though my batteries are sealed. Is that right?
I’m not sure all my batteries are working properly as recently the power has been dropping earlier in the evening, even though I’ve just had 12 hours of unbroken sunshine. Within an hour of morning sunshine all power is working and within 2 hours the Prostar is showing 13.7v
What can I do to test them and can I repair them if necessary?
I have no mains power but access to a generator which I use solely to pump water from my well to the polytank so having a working system is quite vital. Any help that anybody out there can offer will be more appreciated than you will ever know!

jcheil · February 2014

Re: 12 hours of unbroken sunshine for 3 hours of light can't be right....

The best setup IS to have the + or - from battery 1 and the other to battery #4. Especially with that many batteries in parallel (which has complications in itself due to the difficulty of getting an equal charge to each battery). The inverter and charge controller are fine the way they are connected.

However the biggest problem you have is that you are likely right in that your batteries may be a shot.

If your inverter is beeping and shutting down due to low voltage then that means your battery bank is WAY below what it should EVER get to. You never want the bank to get below 20% state of charge and 50% is the recommended max if you want to get the most out of your battery life. A battery that can show 13+ volts at charging but suddenly cannot hold a charge after the sun sets is a sure sign that the bank is in trouble.

The fact that your lights go off but the fan still runs implies that your lighting load is a lot more than your fan load.
Are you using energy efficient light bulbs or old-school "heaters with the side effect of light" bulbs?

Some things to help us help you:

What are your loads? Example, (2) 14w lights, used 7 hours per day, etc.
What are the AH rating on your batteries and their age/brand?
What battery charger do you have? (for when running on the generator)
What is the total wattage of your solar and the configuration (number of panels and the model number or specs on the panels)?

westbranch · February 2014

Re: 12 hours of unbroken sunshine for 3 hours of light can't be right....

Please add a sig line to your profile, with as much detail as you have about each component ( make, model, age, etc) in your system, this will help us dig into your situation without guessing.

ILFE · February 2014

Re: 12 hours of unbroken sunshine for 3 hours of light can't be right....

First, welcome to the forum, pebble.

I currently have four (4) 12v batteries connected to a 1,500 watts inverter, and to a similar controller, the ProStar 30m (with the meter). I have them wired like method #3 on THIS PAGE. The four batteries have #6 awg wires going from them to the positive and negative buss bars.

From the buss bars, two (2) #6 awg wires connect to the "Battery" terminals on the controller. The sensor wires are connected to battery #1 in the bank, if you are interested to know that. (The image below was taken prior to me connecting my inverter, which is connected similarly, via two of these JUNCTION POSTS.) I have two cables going from each battery to its respective junction post. From there, I have two cables connecting the junction posts to the inverter.

In your case, your batteries are wired as in method #2, causing them to not drain, or charge as equally as possible, I imagine? I would rewire them like method #3, and try to charge them up with the generator. Do you have access to a 40 ampere 12vdc charger?

pebbleclur · February 2014

Re: 12 hours of unbroken sunshine for 3 hours of light can't be right....

My bulbs are energy efficient 25watt bulbs, used sparingly - ie. I don't leave lights on for no reason.
I am away from the site at present so the rest is based on memory (like I say, I'm a novice and don't realise what information is needed)
The batteries are 12Ah batteries bought at different times as I can afford them - 2 were bought in 2007, 1 in 2010 and one in 2011. I cannot remember the brand but they are all the same
I don't have a battery charger except the sun
I have picked up the solar panels as and when/where I can. I have 4 (I did have a 5th, 20watt panel but that was stolen last year). There is one BP 80watt panel, and 3 40watt panels, the make of which I don't know)

pebbleclur · February 2014

Re: 12 hours of unbroken sunshine for 3 hours of light can't be right....

Thank you for that - the battery connection explanation makes a lot of sense and gives me something to try. I don't have a battery charger but if I can borrow one, do I charge them in that configuration or should they be charged individually?

jcheil · February 2014

Re: 12 hours of unbroken sunshine for 3 hours of light can't be right....

pebbleclur wrote: »

My bulbs are energy efficient 25watt bulbs, used sparingly - ie. I don't leave lights on for no reason.
I am away from the site at present so the rest is based on memory (like I say, I'm a novice and don't realise what information is needed)
The batteries are 12Ah batteries bought at different times as I can afford them - 2 were bought in 2007, 1 in 2010 and one in 2011. I cannot remember the brand but they are all the same
I don't have a battery charger except the sun
I have picked up the solar panels as and when/where I can. I have 4 (I did have a 5th, 20watt panel but that was stolen last year). There is one BP 80watt panel, and 3 40watt panels, the make of which I don't know)

Are you sure they are (only) 12ah batteries? Do you mean 12v batteries? If so, we would still need to know the ah rating of the batteries (or the brand/model). If they are 12ah batteries and you have 4, that means you will only have 48ah total (24ah usable, 36ah in a pinch) which is barely enought to run much of anything.

Example: 36ah x 12v = 432watt hours, which means you could run a single 25w light bulb for only 17 hours before your batteries are down to 25% SOC (th most you ever want to bring them down to without permanently damaging them).

Basic/generic batteries like GC2 (Golf Cart 6v) can last 1-5 years (sometimes more if you are very careful). I am guessing perhaps your batteries are not true "deep-cycle" batteries. perhaps a hybrid (marine type) since they are 12v. I would not expect more than a couple of years of life from them in a solar installation.

I think it is safe to say your batteries are shot.
Also, 200w of solar would be ok if you REALLY did only have 48ah of batteries. But I am thinking they are bigger in which case 200w would not be enough to get them to charge completely each day. And undercharging batteries is almost the worst thing you can do to them.

Also, as you will read here, mixing batteries, especially more than 6 months apart in age, is a bad thing. They will rarely charge correctly/evenly.

But without REALLY knowing the exact details of your equipment and your exact LOADS (and time usage), it would be hard to give a real answer. Perhaps you can visit the site sometime and get a complete list of what we would need to assist you?

ILFE · February 2014

Re: 12 hours of unbroken sunshine for 3 hours of light can't be right....

pebbleclur wrote: »

Thank you for that - the battery connection explanation makes a lot of sense and gives me something to try. I don't have a battery charger but if I can borrow one, do I charge them in that configuration or should they be charged individually?

At this point, it is hard to say, since, as jcheil stated, we are not sure what size your batteries are. Get all the information, specs on your panels, specs on your batteries, watt hours of your loads, and post that information. Then, the gurus here can help you sort your issues out.

Being relatively new myself, I would definitely do all of that, before spending one cent on any new hardware.

12 hours of unbroken sunshine for 3 hours of light can't be right....

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