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elaine2303

Hi Guys.

I have a problem that's driving me nuts. I have a '96 lwb transit camper and am in Spain at the moment. I bought a 50W solar panel and new leisure battery, 96aH I think, both brand new. I also bought a new 15W regulator to control it all. I'm no electrician but I know enough to wire this all up. So I did and was ecstatic when I had power for the lights (I usually wild camp.) and I could run my laptop from it. What I DIDN'T know was that the panel wasn't charging the battery! I was using the power that was in it and now it isn't charging up.

That's not entirely true. I can put the panel on it all day in the sun and there is enough power to light a small strip light for about 10 minutes before it dies! There is obviously power going in but it seems to be draining straight out the other side!

I had a friend look at it as the lights didn't work at all. He is an auto electrician and sorted it no problem, (I'm too embarrassed to tell you what it was but I put my finger in my ear and said RED backwards ...) but he did say there is a residual current on the system but he wasn't worried about it. That was before I installed the solar system.

I have tried everything I can think of. Taking out the obvious fuses, disconnecting various systems etc but no joy. I still have a new system that doesn't work.

Strange things ... First, I disconnect the engine battery when I stop as I usually stay for a while and it is a bit small for the van so drains eventually of course. The thing is, when I disconnect it, the clock keeps going until I disconnect the leisure battery. When I reconnect that, the clock stops working. Secondly, the regulator looks like it's part of Blackpool illuminations! It shows the panel charging strongly (two out of three lights are lit up). But the load light is always lit as well. I have bypassed the regulator and run the solar panel straight to the battery. No joy.

So, ladies and gents, can anyone suggest where I should look? It can't be rocket science to sort this but it's beyond a little old English lady ... and it's driving me insane keep connecting and disconnecting it every day just to get 10 minutes worth of light and charge my phone occasionally.

Thanks
 
Can you post up any links to the panel and regulator. Also are the two batteries linked in anyway ? Will try and narrow down the problem but a 50W panel is going to struggle to charge a big battery in just daylight hours. cheers P&S
 
Hi and thanks for getting back to me.

This is the link to the panel,
http://www.ebay.co.uk/itm/like/NEW-50W-12v-Energy-Solar-Panel-Polycrystalline-MC4-Connectors-TUV-ISO/281615378863?hlpht=true&ops=true&viphx=1&_trksid=p2050601.c100103.m2451&_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20140721095842%26meid%3D57f89a1103dd4ced9238e775a2dd7e7d%26pid%3D100103%26rk%3D1%26rkt%3D4%26sd%3D281615378863%26clkid%3D4655632491490867957&_qi=RTM1889389

This to the regulator,
http://www.ebay.co.uk/itm/10A-15A-20A-30A-12V-24V-MPPT-Solar-Panel-Battery-Regulator-Charge-Controller-G-/390993635642?pt=LH_DefaultDomain_3&var=&hash=item5b0909693a

The batteries are linked through a controller which charges the leisure battery when the engine is running and after the engine battery is full. I have taken out the fuse to test this. It made no difference.

I appreciate that a 50W panel is not big but as I take very little power out of the leisure battery, it should only be topping up and ought to cope quite easily. The neon strip lights (there are 3 small ones which I use) take almost no power and the phone and a couple of AA or AAA batteries are also not a huge drain. The leisure battery should be pretty much full all the time but ...
 
A 50W solar panel will generate an average daily charge of 250W/h. This would provide enough power for an average daily consumption of 210W/h. The solar system will generate some losses. Mostly in the charge controller and the wiring. Car batteries are also self-discharging. You need to keep the batteries within at least 20% of the total output. If you are changing 12V DC to 240V AC via a inverter than there are even more power losses. The average inverter draws 10-20% more power from the battery than it actually provides at the output. A 50W solar panel typically will just trickle charge the batteries to keep them topped up under no load. I’ve got a feeling you will need at least 100W of solar power to keep your system ticking over. To give you an example, a 100W solar panel normally produces 4-5A per hour in bright sunshine. If you have a 100A/h battery, this will take approximately 20-25 hours to charge from 0% to 100%. Therefore a smaller 50W solar panel would take twice as long to charge the same battery compared to a larger 100W solar panel.

Have you got the details of the two batteries?
 
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Hi,if you suspect a connection between the leisure battery and the vehicle battery,you need to find it.

It may mean your little solar panel is attempting to charge both!

Is your "Charge controller" directing charge from the vehicle alternator to your leisure battery,a fancy unit,or my old pet hate,the "Voltage switched split charge relay"?

Kami has given you excellent data regarding your inputs and outputs,but you will probably need to measure actual charge rate in use,in amps.

I have done a lot with these type of systems,and it can get interesting,as you dig through the various components,all fitted to the same vehicle,yet spanning up to five decades.

At least you have the opportunity to use that wind-up radio from your nephew...:icon12:
 
Guys, thanks for your help. To try to answer your questions ...

The batteries are a 60aH (I think) for the engine (yeah I know ...) and an 80aH (I think) for the leisure side.

Kamikaze, I appreciate that a 50w panel is not going to do much but as all I need is lights and some power to keep the phone charged when it is low, it ought to do the biz. As I said, I am in Spain at the moment and am coming home in May to do my own conversion, hence the small panel. I will add more when I know what system I want to put into the new van. At the moment I am just putting the panel on when I'm at the van and letting it charge the battery without using anything from it. Everything is disconnected at present and I am using solar lights. Romantic but I can't see a damn thing ...

PEG, the two batteries are connected via, and you will love the technical terms here, a small black box with a 10 amp fuse in the top of it! I haven't looked to see what it is but I will. I have had the van for about 7 years. The conversion was done by a Rolls Royce engineer who was pretty good with the solid stuff but a sparky he certainly ain't! He told me it has always been a secondary job for the alternator to charge the leisure battery, the engine battery coming first. I have no reason to doubt this. It has only been since I have been staying in one place for a while that things like the clock working on it's own have come to light.

So, in summary gents, I think the charger/regulator between the batteries isn't the problem.
I appreciate that there is power loss in all electrical systems and the more parts there are to it, the greater the loss. I don't use an inverter to charge the phone or any small batteries. They are charged via the old cigar lighter connection, either straight from the solar panel via the direct feed connection or from the leisure battery if the panel is not connected. Again, very little power take-off.

I am hoping I can get the leisure battery charged up over the weekend but I am still scratching my head about the lights on the solar panel regulator. Does this take power to run itself? I don't see why it should but it seems to be the only explanation. I will check the charger/regulator between the batteries to see what it is and get the precise size of the batteries for the next time.

Again gents, thanks for your time. I know it is sometimes difficult talking to someone like me as a little knowledge is a pain! I will do my best to keep in mind that I am the idiot here ... If I forget you can give me a gentle reminder ...

Have a good weekend and I'll talk to you soon.
TTFN
Elaine
 
Just had a look at the details you posted. The instructions appear quite detailed and it looks like you have a good selection of lights on the controller to tell you what is happening. SO, when you connect it up in sunlight do you get the battery charging lights as per insttructions? cheers P&S
 
Hi plugs.
As far as I can tell yes, but I'm confused by the green "Load" light on the right. Today in the sunshine I had all 5 lights lit brightly. Starting from the right, the green light to say the panel was connected, the three red lights to say it is banging power into the battery and the green Load light, which is confusing because there is nothing connected to the battery with the exception of the solar panel leads.
 
The only thing I can suggest at this stage is get hold of a voltmeter, put it on DC range around 20V range and put the leads on the battery terminals and measure the voltage when the sun is out and the regulator says charging. Above 13V would be useful, above 13.5V very nice and 13.8V pretty good but I doubt you will get this. The battery charging current is a direct function of the voltage applied across it and the speed it will charge. If, sadly, it is around 12.5V, then not much is happening and you need more umph
 
I’ve done some rough calculations, and assuming a 20% inefficiency within the charging system and six hours of quality charging time a day, it would take four and a half days to charge the leisure battery. And like plugsandsparks said, that is assuming you’re getting 13.8V while it is charging. You could just go for a half hour drive in the van every four days and charge the battery via the alternator. Just leave the lights and radio off while your lapping up the miles.:yes:
 
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Gents, again, thanks for your time.

Battery sizes are 44aH for the engine and 88aH for the leisure battery. (I need another 44aH at least for the engine)

I think things are improving as I put the solar panel on the leisure battery for a couple of days and didn't bother to see if there was any charge in it. Yesterday I came back after being out for most of the days and flicked on the lights ... Illumination! It seems there is quite a bit of charge in the battery as the lights were on for about 3/4 of an hour, which, until now, was only happening when I was attached to the mains. The only thing I did differently was to rewire the solar panel with a heavier duty copper wire instead of the cable which was on it. I just needed to move it around to the side of the van and this seems to have made a difference. Maybe there was a dickey connection but I will see if I can get a voltmeter reading.

Thanks for those calculations Kami. On the weekend's result, I think your figures would probably work. As to the alternator charging it, half and hour driving round every four days or so, I may as well save the brass I'd spend on diesel and buy another panel! Much easier ...:grin:

Still ain't found that pesky residual leak but if I get this much power in two days, perhaps it won't be such a problem and I can bite the bullet until I come home in May.
 

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