house hold solar panels

[maverick01]

A mate of mine has upgraded the solar panels on his house and he would like to fit a few to the roof of his caravan.

My concern is he thinks each panel puts out roughly 40amps and i cant seem to find a 40amp solar controller.

What does he need exactly to utilise them camping?

Maverick01

[bully]

Yes there are 40amp controllers but probably the main concern would be that they are probably 24volts. Not sure if they are or not but it would be worth making sure.

[HKB Electronics]

40 amps per panel seems a tad high?

[fridayman]

I have house panels in my setup and they produce up to 36v which limits which controllers can be used just as much as the current. I went for a 45a mppt controller to run 2x185w panels.

[Snapman007]

I'm using 2x190 watt suntech house panels. Jetcrew put me onto a Steca Solarix controller which does the job fine for my panels.
 

[maverick01]

This is the info on the panels.

Maybe someone can point him in the wright direction

[fridayman]

This isn't a very efficient panel, putting out 5A max, so the current won't be a problem for most controllers. But look at the voltage. Many of the common controllers like ctek etc won't work with 37V.

[maverick01]

So do i tell him to not worry about it?

Maverick01

[gronk]

Panels are free, so if he can get a controller that can handle the voltage for a decent price, why not ?

[maverick01]

But if there only putting out 5amps then is it really worth it considering he has roughly 400amp in total with batteries in the caravan?


Maverick01

[Snapman007]

I think you'll find they are a 24v panel similar to mine here;
http://www.energymatters.com.au/suntech-solar-panel-190watt-24volt-monocrystalline-p-2698.html

If that is the case and he can use the Steca Solarix, I think I paid around $320 for mine plus cables and connectors.

[maverick01]

Thanks.

Would it be worth all the hassle or is it easier to buy a package from a reputable company?

[gronk]

Depends on whether he wants to spend some money, and for what he wants to do, buying separate would be the way to go.

2 X 200W panels off e bay ( rich panels ) are approx $210 each, but you get 10A output instead of 5A, and a controller at approx $30 to $100, depending on quality.

All comes down to space and money, for 400a/h of batteries, my ideal output from panels would be 40A, which would be 4X200W panels, which is 60kg's in weight, which is approx $850 worth and finding where to put them as well ??

So, you see where it has gone......from a couple of free panels to a system that is ideal !!

[HKB Electronics]

The panel is rated at 190W, if you purchase an mppt that can handle the input voltage
and has a 12V output the you should be able to extract the 190W, around 13 amps
at 14.4V

Cheers

[jetcrew]

The panel is rated at 190W, if you purchase an mppt that can handle the input voltage
and has a 12V output the you should be able to extract the 190W, around 13 amps
at 14.4V

Cheers

This is right on the mark..

Your mate needs a type 2 MPPT that can accept a higher PV modulate voltage and step this down to a lower battery voltage. so it is a reverse DC/DC in a sense. it will take the 5A @24v and spit out 10A @12v .

Crude example but you get the point.

this style of set up is very common in RAPS where you use a 48v panel panel arrangement and drop this down to a 24v batt bank.

as Snapmann has said you will need a Type 2 mppt  and these start at $320+ right up to 1K 

Jet