Solar panels and regulation of current

[xelasnave]

Well I am pretty sure that I blew up my regulator that ensures the batteries are not cooked by too much charge from the solar panels...I am not sure what happened other than the big spark but I think the power take off shorted with something...lesson...disconnect the batteries where playing around. I didn't connect anything in the wrong place but clearly two hot unprotected wires came in contact with something...if I put a wire in the wrong place I could tell you..e.g. positive in a negative connector sort of thing.

Anyways I would like to run by anyone who can tell me what I think may work will not cause a fire or ruin the batteries.

Specifications. Well a little problem here as I have to guess with some of the numbers.

Panels..two that are probably 100 to 120 watt .. 3 batteries..12 volts each
in parallel and no real indication of amp hours other than there is a 70 in their brand name ( I have searched but have not turned up a thing) and they look about right for a 70 amp hour size..they say they are a calcium battery which I am not familiar with and I think when I looked a month ago I found nothing..not sure if I specifically looked for a calcium type or if I gave up not finding the manufacturer etc...they say they are made in Korea.

So no regulator is the problem. I tested it with the multi meter and I know it is not functional.

My thought was to run the solar panels direct to the battery and then run my fridge ( an Aldi camper thing ) from the inverter ..again no numbers for the fridge but I reckon 50 to 60 watts...and also run a small fan which has no numbers but I expect it would be 40 watts..it's a car type of thing...straight off the battery....the idea being that between the fridge (running at max seeking to reach -18 degrees possibly -20?) and the fan both taking a fair bit of power that the batteries run little risk of cooking...also to run then down at night to say 12 volts...so they need a full charge the next day.

I do have s smaller controller rated at 10 amps which I wonder could be used and if so what is the worst that can happen...I guess if the panels pull 20 amps and it is 10 it would die..explode maybe????

Or do the above as to inverter fridge etc and disconnect the panels for a couple of hours around mid day...particularly if I used the smaller regulator. Perhaps check with the multi meter and shut down when the batteries reach 13 volts..I expect they can go to 13.5

I did pull the presumably stuffed regulator apart and noticed some little buttons similar to but not the reset button that did not work to bring it back from the dead....on the case it mentions a fuse but I am sure there is no fuse.

Also I could plug in the lap top phone and tablet as well in an effort not to let the battery cook...usually you don't seem to get enough charge for your needs but I am pretty sure the regulator never let's anywhere near the panels output to go to the batteries...Well say the panels are putting out approx 20 amps when doing their best and being approx 200 amp hours in the battery is is already around a safe charging rate which I take to be 10% of the battery capacity ... then there are the interruptionswe call clouds and the trees..they probably don't get Sunlight after 3 pm.

I guess I will try it unless someone points out a major problem.
Alex

[xelasnave]

Here is details on the small regulator and a shot of one of the batteries.
Alex

[xelasnave]

Well luck is always on my side..I remembered there is another solar set up in the old shed I was going to set up as an observatory style home...I changed my mind when the lightning hit the house and opted for the valley by the dam..but I had forgot about it..so much to do...in the mean time I am not going ahead with the no regulator plan and using the Genny to top up the 120 amp battery I am using (the astronomy unit) so getting by.
Alex

[pmrid (Peter)]

Alex, those batteries seem to be automotive types. Those are the ones whose output it usually rated in terms of CCAs (i.e. cranking amps). These are 770 which puts them at the higher end of the auto range such as you might use on a larger family car or something similar.

That makes them fairly unsuited to use as storage for solar power.

Also worth noting is that an unregulated solar panel of a nominal 12 volt DC output will actually deliver closer to 19-20 volts DC of open circuit power. Have a look on the back of the panel and the numbers should be there.

Most 12 volt batteries have a recommended charging range which may go as high as 14 volts but no higher. Manufacturers will usually recommend that the charging voltage not exceed that range otherwise the battery will be damaged.

I therefore would urge you to reconsider your "no regulator" plan. It would almost certainly end in tears.

Peter

[xelasnave]

Thanks Peter.
Here I am thinking I have some flash batteries and clearly the folk putting them in knew less than I do..no wonder they were not turning up on the Rainbow Power web site.
The panels are screwed down on the roof and I can't climb up there.
I don't know where to go from here...I need a new system really except panels.
Thank you so much for your input as it has really helped me..I was only today going to take the regulator and inverter out if my old shed,place whatever...I won't be doing that so you have given me a day of life..thank you.
Alex

[pmrid (Peter)]

Originally Posted by xelasnave

I don't know where to go from here...I need a new system really except panels.

Cheers Alex. I do enjoy playing with solar and wind power systems.

Getting a new regulator is not an expensive thing. EBay lists a whole gamut of them from $15-50ish. Just search under "solar regulator" and remember you're dealing with 12 volts DC. Depending how many panels you have, you will need to decide on the Amperage you need. If you only have a few panels, 20-30 Amps should be fine.

These regulators are easy to wire into your existing solar panels. They will have 1 input from the panels and 2 outputs - one to battery and one to "load". You can ignore the latter. Just run a connection to the batteries with the correct polarity and they will happily charge away. If you want to take power out of the system, connect an inverter to the battery direct and you'll have 240volt AC power - or 12 volt DC if that's what you want.

Peter