Solar panels

SteveG

SteveG

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I have panels on my house but would like advice on using them on the van? How do they connect to the electrical supply of the van, are they a DIY or dealer fit? Any advice would be gratefully accepted :-)
Hope everyone's enjoying their festivities!
 
Your domestic panels are a higher voltage than those suitable for your van, they are connected to a grid tied inverter that converts your solar array into a voltage suitable to feed back into the mains system

For your van you need panels that can be used with a 12 volt regulator that will then charge your leisure batteries. They will not feed your mains sockets.
 
I know 12v panels are needed not the ones on my house! ;-) are they a DIY job do you think?
 
Looks a neat job from the photo :-)
 
Yes any competent DIY'r can do this

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fitted an additional panel to mine so that the panel lifts on and off. wired to controller then to leisure batteries. The directions were in good English and very clear. If I'd realised sooner on this recently acquired van I could have possibly wired it directly to the MH EC500 PSU same as the permanently fixed one. Its only a 42w panel but when angled southwards I reckon it matches the output from the 100w fixed panel.
 
Only real strong advice I would offer is to get the very best controller you can buy
Skimping on the controller is false economy as a lot of the power generated by the panels will end up being wasted
 
My controller is a sunsaver 20.

My intention is to wire em in series! I.E. pos to neg on next panel and so on so should not have to join wires or make any holes.

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ksebruce said:
My controller is a sunsaver 20.

My intention is to wire em in series! I.E. pos to neg on next panel and so on so should not have to join wires or make any holes.
Click to expand...
RTFM
If its a Morning Star corporation SunSaver controller then its uses PWM technology and can only take a input of 25 Volts, so you must connect the panels in parallel.
To enable you to connect panels in series you need the more efficient MPPT techology.
 
ksebruce said:
My controller is a sunsaver 20.

My intention is to wire em in series! I.E. pos to neg on next panel and so on so should not have to join wires or make any holes.
Click to expand...
I dont "think" you can do that
In series will step voltage up
So if you linked all 3 in series you would have 36 volt
Would that not decrees Amps to about 8 or would controller take care of that
I was not told not to do it but I may be wrong elecctricery is not my thing
It may be my controller that can't handle it
 
It can be done & can usefully extend the time of year panels produce something meaningful, especially if you will be anywhere in Northern Europe.

But - you must have a MPPT controller & it must be capable of handling the SUM of the voltages produced by each panel. That leaves you with a fairly short short-list of fairly expensive controllers, but it's the way to go if you want to wild camp out of season. It can't work miracles though.

Something like this.
 
Have decided to wire in parallel and our 20 amp controller will be ok at this time of year.
Will just link the pos together from panel to panel then the negs and to the controller
Will buy a 30 amp mppt when we get home.

Thanks
 
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Something like Broken Link Removed can be used to connect up to an existing installation.

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Taran_Las said:
Something like Broken Link Removed can be used to connect up to an existing installation.
Click to expand...
excellent
vin0114 said:
fitted an additional panel to mine so that the panel lifts on and off. wired to controller then to leisure batteries. The directions were in good English and very clear. If I'd realised sooner on this recently acquired van I could have possibly wired it directly to the MH EC500 PSU same as the permanently fixed one. Its only a 42w panel but when angled southwards I reckon it matches the output from the 100w fixed panel.
Click to expand...
Connection should be to the battery first and solar panel last

ksebruce said:
My controller is a sunsaver 20.

My intention is to wire em in series! I.E. pos to neg on next panel and so on so should not have to join wires or make any holes.
Click to expand...
an autosensing 12/24v controller would handle them connected in series.
 
Wildman said:
an autosensing 12/24v controller would handle them connected in series.
Click to expand...
Err NO!
The autosensing bit is on the battery side, so with a 12V battery you need a maximum of 36 cells in series, panels with 36 cells are usually refer to as 12V panels.
A MPPT controller handle higher voltage panels or panels in series. The controller manual will specify the maximum wattage of the panels that can be connected.
 
Oops, thats what goes of replying with a thick head in the morning unless of course your batteries are connected in series but the outputs are taken across one battery only.
 
The instructions for my regulator says batteries last! i am now lost!
 
Just reread the instructions.
Two pages on it says first!!! Must be a misprint on the earlier page!!!
So will go with first!!!
 
The MPPT controllers that we have, and Andy (techno100) have an operating input voltage range up to about 33V and a 'Do Not Exceed' voltage of 55volts.

We tried series connecting panels a couple of years ago, when we were fitting the trailer out. It didn't work.

The current build has 4 X 100W panels feeding two MPPT controllers. We originally planned for a 220AH leisure battery but two more 6V 220's came along for free so we will have 440AH worth of batteries in total.

Panels picture:

Broken Link Removed

Previous build on the trailer (which we still have)

Broken Link Removed

Andy was the source of much help and information when we did the trailer, for which we are very grateful.

Peter
 
Peter A Forbes said:
We tried series connecting panels a couple of years ago, when we were fitting the trailer out. It didn't work.
Click to expand...
@Peter A Forbes - what was the problem with the series connection?

Which controller did you have? The same 33V ones?

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For what it is worth I have never tried the series option despite that mppt being marketed as capable. I have plenty of panels laid up so I might connect a set up next month on my decking and see what develops .The reason I didn't go for series was the problem of having 3x100 watt panels which in series would be far too high a voltage.

This is the regulator Broken Link Removed

As you will see it can handle a maximum OPEN circuit voltage of 50
12 volt panels have open circuit voltages of under 22volts so 2 in series should work in theory
 
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TheCaller said:
@Peter A Forbes - what was the problem with the series connection?

Which controller did you have? The same 33V ones?
Click to expand...

Yes, the same as Andy has.

Max MPPT input is 33V, Absolute Max withstand input 55V.

The normal panel would output 18V or so, with two in series you'd straight away exceed the MPPT voltage for the controller and it shuts down.

Peter
 
Where does it say 33volts in the manual Peter?
It quotes max open circuit voltage 50 which is fine for series
 
I see now you have the MKII model
The later one and current model is 15 to 37 volts mppt.

EDIT I see from your picture in the other thread that you have a MKII on the left & a MKIII on the right. The later model also has an always on display and a backlight when needed.
 
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Techno100 said:
I have plenty of panels laid up so I might connect a set up next month on my decking and see what develops
Click to expand...
It would be a good time to run some trials while there isn't a lot of sun about.

Comparing the output from the same two panels wired first in parallel then in series while the sun is low intensity should show if it's worth doing - or more precisely, whether it's worth paying the extra for a regulator that will take the higher input voltage.

As the sun increases in strength, there should be a period when the series wired pair begin providing sufficient output voltage to start the charging process while a parallel wired pair wouldn't produce enough to start charging.

Once there is sufficient sun for the parallel wired pair to start charging as well, I'm guessing that there is little difference between the two methods, but I don't really know.

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