Solar and batteries

[wyleyrabbit]

We have 2 x 110W solar panels on our 3055RL, and 2 x 6V golf cart batteries, and the batteries don't seem to be charging. Our unit is stored outside and we've had some nice sunny weather here this past week. Nothing in the trailer is on, from what I can tell, so nothing should be draining power from the batteries. The trailer has been locked up and it's been a week since I was last there.

Also, last week I drove the trailer around for almost 4 hours, and it was obviously hooked up to the truck. Even with that, the batteries didn't charge up as much as I'd expect.

According to the solar regulator (by "Go Power!"), the battery level is at about the 60% mark on the meter, and the display indicates 12.3 volts.

It's quite overcast today, so we were not getting the same as a bright sunny day, but the display shows 2.2 amps coming from the panels. Since we haven't used any power over the past week, even with the shorter days (we're currently about 11 hours between sunrise and sunset) and a mix of sun with clouds the batteries should have charged up this week, shouldn't they? Even if it was only 1 amp coming in off the solar panel for only 8 hours per day, that's 8 amps a day x 7 days = 56 amps should have gone into those batteries...right?

So why are my batteries not full? Is there something wrong with either the solar system, the converter, the solar regulator, or the way it was installed? Something just doesn't seem right. Obviously I'm a noob, so any information would be very much appreciated.

Chris

PS - I've attached a couple of pictures here; sorry about the quality, they were taken with my phone's camera and I don't have very steady hands.

 

[grizzlygiant]

Based on my experience with my solar battery charger, I will offer a few gusses:
#1. There is a light left on somewhere
#2. The furnace thermostat is in the "on" position
#3. There is a residual "parasidic" draw even with everything off--detectors, refrigerator, convertor.

To eliminate all of these I installed a battery cut-off switch that disconnects everything except the solar panel which goes directly to the battery post. A side benefit is that it eliminates anyone messing with the jacks while in storage.

You certainly have enough solar power to keep the batteries well charged. I use a 15 watt panel and it keeps the batteries (2x6v) at 100%, even in the snow!

 

[wyleyrabbit]

Thanks for the info. When your batteries are charged, how many volts are they showing? My understanding is that fully charged batteries should be somewhere around 14 volts.

I'm certain that there aren't any lights on anywhere. The fridge is off, the CO2 detector uses batteries. I have tried flipping all the breakers off, but honestly I'm not sure they even do anything unless there's AC hooked up.

I've checked the thermostat, it's definitely off. Well, it doesn't really have an "off" position, just "auto" and "on". Switch is on "auto" and the temperature is turned down.

Does the Bighorn come with a battery disconnect switch somewhere? If not, are they difficult to install?

 

[Seaulayter]

I have a similar setup as you and there are several devices that draw off of your batteries. One is the TV booster and another is the propane gas alarm. It was really simple to install a main cut off switch and like 'grizzlygiant' my solar panel is wired to the battery side of the cut off switch.

 

[sailorand]

Your batteries might be gone. Put a load test on them to see what happens.
Full charge your batteries should be about 13.6 volts.
I have a load tester if you need one.

 

[timk]

Chris,
I would check your wire sizes. It is possible that due to line loss and voltage drops due to line loss, there might not be much getting to the batteries. That certainly would explain driving and not charging quickly.
What I understand, the only way to check your charge status with a voltmeter, is after the batteries have settled down a while, with no load or charge activity. I remember full at 12.6 volts. While charging volts should be 14 or so.
If your wall mounted meter has a shunt at the batteries, you can trust that. If not its pretty easy to check the amps at the battery with a small cheap amp-meter. Thats also a good way to check for parasite loads.
TimK

 

[wyleyrabbit]

How many hours of driving with the trailer should it take to fully charge the batteries from a 60% starting point?

 

[wyleyrabbit]

I just got off the phone with Carmanah Technologies tech support, and he said that this issue sometimes happens with very new batteries. He suggested that the issue might be as simple as cycling the batteries a couple of times. Apparently, I should turn on the lights and such until the batteries drop to something between 11.5 and 11.7 volts, then turn everything off and let them charge up for a few days, then do it again.

He said it's also possible that one or both of my batteries are defective or something but to try this first.

I'll post here and let everyone know how it goes.

Chris

 

[wyleyrabbit]

Today I drove to the farm where our trailer is stored and went through everything carefully looking for anything that might be drawing power. I thought that maybe there was a light on in one of the storage compartments, closets, or something. Nope. Turns out the TV antenna booster was on...aha! It came that way from the dealer. I turned the booster off. Hopefully this was the culprit.

Does anyone know how many watts or amps the antenna booster draws?

Now the only thing drawing power from what I can tell is the propane alarm. There seems to be no way to turn it off; I pulled the fuse for it, and it complained rather bitterly (and loudly), so I put the fuse back in.

In an effort to run the batteries down a bit more to give them a cycle, I turned every light in the trailer on and also turned on the furnace fan. I took the batteries down to about the 20% mark (~ 11.1 volts). I then turned everything off and waited for about 30 mins, and the panels already had the batteries up to 12.0 volts. I guess that's a good sign.

I also did some hunting around for either a battery disconnect switch or a fuse, but found neither. Seems to me there should be at least a fuse, shouldn't there?

I'll go back and check the batteries tomorrow and see where the charge level is on the batteries.

 

[ibrick]

My battery disconnect switch is located in the basement on the front wall right next to the battery/pump compartment. Round hole with plastic flange for a key. Don't know if it was an option, as I bought used.

 

[grizzlygiant]

The battery disconnect is not a factory item; you have to add it yourself. The switch can be purchased at most any auto parts store for around $20. It is very easy to install.

BTW, flipping off breakers does not disconnect 12v circuits; only 120 v circuits.

You indicated that your panels brought your batteries from 20% to something like 80% in 30 minutes? Something is not right because your solar panels do not put out that many amp hours even in bright sunlight to accomplish this task.

 

[DennisZ]

Chris

The Bighorns do not come with a battery cutoff switch. The antenna amp should be drawing something less than 100ma, usually much less. I doubt if that is your problem, your solar should have more than enough power to have fully charged everything by now.

Dennis

 

[timk]

Chris,
You might be expecting a little too much from your panels.
Our antenna draws .04 amps, our hot water heater draws .22 amps, and our co2 detector draws .04 amps. Well you get the idea. These little things could easily add up to an amp. If your only putting out 2.2 less that 1, that means your only getting a little over 1 amp back to the batteries. Two 6v batteries should be about 220 ah. So if your down to 60% you have to put back about 88 ah to be fully charged. Keep in mind that the little draw goes on in the dark, while the charge goes in only in good light.

West Marine is a good source for good switches if you find you dont have one.

 

[wyleyrabbit]

Rick,

Any chance you can take a photo of that switch and upload it? Perhaps I just don't know what I'm looking for.

Chris

 

[wyleyrabbit]

Well I'm stuck. I don't understand why my batteries are decreasing voltage and charge with every day that goes by that I don't use them. I thought I might have figured out the problem when I found that the antenna booster was on. I guess not.

I guess I need to add a battery disconnect switch (Why the heck didn't the dealer install this at the same time they nailed me for almost $3k for the solar panels, the regulator, and the batteries??? ARGH!). Is this likely the issue? Is it simply that the converter, the propane detector, and the phantom power used by nothing in particular is the reason that my batteries are worse every time I look at them, even though the unit is simply in storage (outside, I might add)?

My understanding is that batteries are like a 5-gallon (or whatever size) pail, with a spigot on the bottom. My solar panels are supposed to be adding to the bucket, and in theory the spigot is turned off; therefore the bucket should eventually fill up. The solar panels have been installed with the batteries for almost a month now, and seriously...every time I visit the trailer the batteries are in a worse state than the previous visit. I'm stuck. Maybe I got a defective battery or regulator???

Chris

 

[jmgratz]

I know very little about solar stuff but have you checked the batteries. A battery will not hold a charge or take a complete charge if it has a bad cell or is low on water. Not long ago I bought a brand new battery that had 2 bad cells. It would charge to 70 percent and then would not hold the charge. Just a thought...

 

[wyleyrabbit]

I will check the batteries today. What is the procedure for doing that? Checking water levels can be done visually I guess. But I have no idea what else to check. I have a good meter so could check voltages individually.

I don't yet have an inverter.

Chris

 

[wyleyrabbit]

Does my Bighorn come with some sort of fuse that I could pull that would achieve the same as a battery disconnect switch until I can get one of those installed?

 

[sailorand]

there is no disconnect unless you just take the battery lead off the post

 

[ibrick]

Sorry Chris, It's over on the left coast and I won't see it again until April some time.
But I did find some info by searching for posts from Gary, the previous owner.
//heartlandowners.org/showthread.php?t=4628
Seems it was a $200 option installed by the dealer, I'll see if I can find a picture of it.

edit- opps, not sure if $200 is correct. Looked further into Gary's posts and checked out the dealers selection of switches and nothing matches what I have.