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Fazerloz
14-10-2013, 16:09
Some of these panels have been on sale today at a auction house near me going for between 20 to 40 .
LG250S1C-G2 LG Electronics
JKMS250P-60 Jinko
PV-MBA1AG247 Samsung

Would these panels be suitable for putting on a van roof for the 12v system and if so what would be a suitable controller, and if not for what reason.
I noticed there were more panels to one side no doubt to be auctioned off at some future date.
:cheers:

john t
14-10-2013, 16:16
Could run a house on 240w solar panel, i have a 120w on my m/home and runs all my 12v appliances including tv.!
I'm sure someone will be along shortly with more knowledge and info that i know.!

jt

Fazerloz
14-10-2013, 16:20
I would have bought if they were 120w but dont know if 250w are suitable.

maingate
14-10-2013, 16:46
It is not the wattage that is important but the voltage produced. You need to get a look at the details on the back of the panels and read the voltage values. An MPPT controller may be able to cope with a higher voltage but there will be a limit.

Wooie1958
14-10-2013, 16:54
A quick look at the spec sheets says all 3 are 24 volts panels.

torwood
14-10-2013, 17:34
A quick look at the spec sheets says all 3 are 24 volts panels.
That's correct, some panels have two circuits and are wired in series to give 24 volts and can be separated, unfortunately these panels are designed as 24 volt panels and will cook your batteries on a 12 volt system and do other damage to your electrics.

maingate
14-10-2013, 17:48
Not so.

An MPPT Controller can handle voltages above 24 volts. There are people using them nowadays.

torwood
14-10-2013, 17:55
Not so.

An MPPT Controller can handle voltages above 24 volts. There are people using them nowadays.
Methinks you miss the point, while a controller can handle 24 volts, a 12 volt panel will give 17 volts off load, your 24 volt panel will produce nearer 40 volts off load. If your vehicle and habitation electrics are rated at 12 volts, your battery is 12 volts then a 24 volt panel will be way over the systems capacity and will lead to damage. Caveat Emptor!

maingate
14-10-2013, 18:16
I didn't miss the point. Some MPPT controllers can handle much higher voltages as I said in my first post.

Check this link and read about 6 lines down and all will be explained.

http://www.midsummerenergy.co.uk/buy/MPPT-solar-regulators/

maingate
14-10-2013, 18:53
OK then, don't admit you were wrong and I was right.

A bit churlish don't you think?

Smaug
14-10-2013, 19:06
Some of these panels have been on sale today at a auction house near me going for between 20 to 40 .
LG250S1C-G2 LG Electronics
JKMS250P-60 Jinko
PV-MBA1AG247 Samsung

Would these panels be suitable for putting on a van roof for the 12v system and if so what would be a suitable controller, and if not for what reason.
I noticed there were more panels to one side no doubt to be auctioned off at some future date.
:cheers:

At that price I would buy a couple - if it turns out that they don't suit (for any reason) it's no problem to flog 'em on is it?

hextal
14-10-2013, 19:09
OK then, don't admit you were wrong and I was right.

A bit churlish don't you think?

I think there's such a thing as being gracious in victory.:lol-053::lol-053::lol-053:

Fazerloz
14-10-2013, 19:24
At that price I would buy a couple - if it turns out that they don't suit (for any reason) it's no problem to flog 'em on is it?

Trouble is I wouldnt get around to selling them and they would end up in the garage with all the other good ideas I have had. Thats why I now try not to buy things unless i no they will work and i can get on with them straight away. Please note the word try.:fun:

maingate
14-10-2013, 19:42
I think there's such a thing as being gracious in victory.:lol-053::lol-053::lol-053:

When someone is asking for advice it is important that they don't get the wrong advice.

We can all be wrong at some time. At least I would admit it and thank the fellow member for providing info to back it up.

Fazerloz
14-10-2013, 19:44
Would anyone be interested if I could get some the next time they come up for sale.:cheers:

torwood
14-10-2013, 19:56
OK then, don't admit you were wrong and I was right.

A bit churlish don't you think?
It's hardly churlish when I am not online 24/7, I dip in and out of the forum, I don't live in it!.

Yes you are right as long as an appropriate regulator is used, you could also drop the voltage in a number of other ways, none of which are appropriate for someone who is not sure of what they are doing, the potential for significant is damage is there in the wrong hands.

Fazerloz
14-10-2013, 20:08
I did ask to be pointed in the right direction as far as a suitable controller was concerned. :cheers:

Smaug
14-10-2013, 20:35
Trouble is I wouldnt get around to selling them and they would end up in the garage with all the other good ideas I have had. Thats why I now try not to buy things unless i no they will work and i can get on with them straight away. Please note the word try.:fun:

I can relate to that.

I would have dived on 'em, but I already have 2 in the garage waiting for me to fit them on the roof of the van.

Fazerloz
14-10-2013, 20:53
If I dont die untill i have all my jobs done i should live untill i am 160 somehow i think some jobs will be left undone.:cheers:

wildman
14-10-2013, 22:34
I could be interested in a couple depending on price and where you are.

Fazerloz
14-10-2013, 22:43
West Yorks as for price who knows its a auction and no idea when they are going in. I dont want to make anything on them .

shaunr68
15-10-2013, 09:35
Numpty question here concering Ohm's law and 24 volt panels which are regulated down to suit a 12v system. I have a decent working knowledge of the practicalities of installing and running a solar charging system in our T4, but struggle to get to grips with the scientific theory behind how all these electrons get around :D

250 watts at 24 volts means the panel will be putting out just over 10 amps peak, right? 250=24 x 10.42

So what are the constants when the regulator steps the voltage down to 12v? Either the watts remain constant which means you're now getting almost 21 amps, woohoo, or the amps remain constant which means the panel is only working at half capacity.

Anyone throw any light on this please?

Andy75
16-10-2013, 15:29
Well the energy won't go anywhere, so you get 12v at the increased amperage. Might not be the 21 amps though, could be 20 or 19, depending on how efficient the controller is, and how close it is running to full capacity.

Rockrat
17-10-2013, 19:32
Unbelievable..
I am googling the net trying to find out what I need to get the 4 solar panels I bought at auction going and came across this site.

I am the buyer off these exact panels..

I have tested them all, they work fine.

Got all 4 for 220 in total... So I reckon I got a good deal

I have a office garden and want to get it work veg on solar... But haven't a clue what I need as well as these... And am now in research mode.

Sorry to OP if he bid, but I was in the room.. Bidding wasn't that bad, I expected them to go higher to be honest and set a limit of 60 per panel.. The most I paid for one was 55 the rest 30 and 35


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