Adding portable solar to existing fixed solar.

Submitted: Saturday, Dec 17, 2022 at 18:40
ThreadID: 145129 Views:4222 Replies:8 FollowUps:10
This Thread has been Archived
G'day All

I have a 110 watt fixed panel running through a redarc 1225d on my camper trailer.
I also have a 120 watt folding blanket with its own regulator I would like to add on occasions.

Is it best to connect the folding blanket direct to the battery through its own regulator to avoid any issues with the other panel and redarc or is it possible to run them both through the redarc without issue ?


Cheers
Gazz

Back Expand Un-Read 0 Moderator

Reply By: Peter_n_Margaret - Saturday, Dec 17, 2022 at 20:08

Saturday, Dec 17, 2022 at 20:08
Because the performance parameters of the 2 panels are probably different, it would be better for the second panel to have its own controller. That controller will do a better job if it is near the battery, rather than on the panel though.
Check that it is a decent controller and move it to near the battery.
Cheers,
Peter
OKA196 motorhome
AnswerID: 642344

Reply By: TrevorDavid - Saturday, Dec 17, 2022 at 20:26

Saturday, Dec 17, 2022 at 20:26
Gazz

Did this recently to a mates van.

If the panels are of similar voltage, wire them in parallel through the Redarc only. The Redarc will see them as one and will use the panel with the lowest voltage for its workings.

Regards

TrevorDavid
dontyajustluvit

Lifetime Member
My Profile  My Position  Send Message

AnswerID: 642345

Follow Up By: Member - Outback Gazz - Saturday, Dec 17, 2022 at 20:46

Saturday, Dec 17, 2022 at 20:46
Thanks TD

I have the fixed panel connected to the Redarc with an anderson plug - so would making a double adaptor anderson plug work if I removed the regulator from the folding panel and hooked it in to the double adaptor ?

Cheers
Gazz
0
FollowupID: 921842

Follow Up By: TrevorDavid - Saturday, Dec 17, 2022 at 21:01

Saturday, Dec 17, 2022 at 21:01
Gazz

Yep

Regards

TrevorDavid
dontyajustluvit

Lifetime Member
My Profile  My Position  Send Message

2
FollowupID: 921844

Follow Up By: Member - Boobook - Monday, Dec 19, 2022 at 10:20

Monday, Dec 19, 2022 at 10:20
If you do that, put in a series blocking diode on each panel, or you can potentially burn out cells of any panels in shade. These are different to the standard bypass diodes integrated into most panels.
0
FollowupID: 921860

Reply By: AlbyNSW - Saturday, Dec 17, 2022 at 20:40

Saturday, Dec 17, 2022 at 20:40
I have the setup you are contemplating and the advise from Enerdrive was as long as the panels are similar in voltage output just run them all through the one controller and it will sort them out.
I have set up a double adapter Anderson plug to connect my portable panel to.
AnswerID: 642346

Follow Up By: Member - Outback Gazz - Saturday, Dec 17, 2022 at 20:50

Saturday, Dec 17, 2022 at 20:50
Hey Alby - haha I just posed that to the previous replier - howz the timing !

Thanks
Gazz
1
FollowupID: 921843

Reply By: Peter_n_Margaret - Saturday, Dec 17, 2022 at 22:26

Saturday, Dec 17, 2022 at 22:26
One of the benefits of a portable panel is to be able to keep it in the sun when the fixed panel is shaded.
Having them on separate controllers will do that better than having then on the same controller.
Cheers,
Peter
OKA196 motorhome
AnswerID: 642347

Follow Up By: AlbyNSW - Sunday, Dec 18, 2022 at 06:32

Sunday, Dec 18, 2022 at 06:32
How is that so Peter? My solar experience is limited but regardless of how many controllers you have wouldn’t whatever the amount of solar energy you are capturing be processed the same?
0
FollowupID: 921846

Follow Up By: TrevorDavid - Sunday, Dec 18, 2022 at 06:43

Sunday, Dec 18, 2022 at 06:43
That’s the argument I guess, but as Gazz’ panels will be in parallel, the back feed into the shaded panel is negligible, I would not even worry about a diode.

Regards

TrevorDavid
dontyajustluvit

Lifetime Member
My Profile  My Position  Send Message

0
FollowupID: 921847

Follow Up By: Nomadic Navara - Sunday, Dec 18, 2022 at 10:22

Sunday, Dec 18, 2022 at 10:22
"How is that so Peter? "

It depend upon the style of the controller. If it is a PWM controller it may not be much of a problem.

If you have an MPPT controller there could be times when two controllers would be an advantage. Multiple panels on an MPPT controller work best where the panels are in equal sun exposure and the panels are similar in characteristic to each other. o doubt you are wishing to use your portable panel(s) when you have parked your rig in a bit of shade. In that case it does not take too much shading to put the panels out of action due to the slightly less output than normal from the fixed panels. However, when panels are a little shaded it does not put them out of action completely. If you have the two sets of panels on separate controllers, the fixed panels will at certain times be still able to contribute to charging the batteries whereas they would have been completely negated by the higher output from the portable panel.

PeterD
Retired radio and electronics technician

Lifetime Member
My Profile  Send Message

1
FollowupID: 921850

Reply By: Member - Outback Gazz - Sunday, Dec 18, 2022 at 10:05

Sunday, Dec 18, 2022 at 10:05
Thanks to all who replied

I rarely spend more than two days in the one spot so the fixed panel does the job but I have a couple trips coming up where I will be forced to sit still for five days lol - so I will take the folding blanket with me.

So now I just need to get my fat boofhead and large hands into tiny spaces for some more wiring lol

Cheers and cold beers
Gazz

AnswerID: 642349

Follow Up By: Peter_n_Margaret - Sunday, Dec 18, 2022 at 10:31

Sunday, Dec 18, 2022 at 10:31
Knowing the specific output specs of the 2 panels would help.
Cheers,
Peter
OKA196 motorhome
0
FollowupID: 921851

Follow Up By: AlbyNSW - Sunday, Dec 18, 2022 at 14:32

Sunday, Dec 18, 2022 at 14:32
One of the advantages of a blanket is they also make a great windscreen shade when in use.

I run two fridges and we found on our last trip on the west coast that we could sit still indefinitely with 100% charge being obtained each day before lunch
We have a 180w fixed panel on the roof and a 200w blanket
1
FollowupID: 921852

Reply By: qldcamper - Monday, Dec 19, 2022 at 07:27

Monday, Dec 19, 2022 at 07:27
Just use 2 controllers and get them in the sun, dont bother trying to achieve theoretical perfection as that is impossible.
When batteries are low or load is high both controllers will go their hardest and when the battery voltage comes up the 2 controllers will switch through their different stages at different times and have an affect on each other but at that stage it doesnt matter as the battery is nearing full, or full enough to last till morning.
I have two seperate systems, the car and the camper, each with their own battery, controller and panel, fridge is in the car.
If the car battery gets low I just link the two together with my 10 metre 6mm(automotive) extention which many here refuse to accept actually works, and let the electrons flow where ever they want. The law of physics sorts that out for me. Both systems charge but the redarc in the car goes into float before the victron in the trailer.
As yet havent run out of power for either the fridge or electric blankets but both of those never get pushed hard at the same time but works for me.
By the way, batteries are an 80ah AGM in the trailer and a 100ah AGM in the car and I consider low to be 11.5 volts while the compressor is running.
AnswerID: 642354

Reply By: NEWPRO S - Friday, Dec 23, 2022 at 20:55

Friday, Dec 23, 2022 at 20:55
If you've ever wondered if it's possible to connect two solar panels to one battery, the answer is Yes... if you do it the right way.
AnswerID: 642384

Reply By: Member - Andrew C11 - Monday, Dec 26, 2022 at 20:15

Monday, Dec 26, 2022 at 20:15
Gazz,

The simplest way is to add an additional MPPT controller, the best are Victron. If you also get the smart controller then you can also Bluetooth to them for data and upgrades, you can also setup a network between them to balance charging needs.
I have two setup like this, one for the permanent panel and one for the external. This way you can get maximum charging from both panels, and if one is in the shade the other will still work correctly (the network allows them to control the charge rate, so if the battery is full they'll start to shutdown).
I'd recommend for a simple setup the 75/15, it'll take up to 260watts, this should be plenty for most requirements.
Not sure if I'm supposed to to recommend, websites but I've brought lots of gear from Outbackmarine. They are a good source of gear and information.

Victron COntrollers

Regards
Andy
AnswerID: 642400

Follow Up By: Member - Outback Gazz - Wednesday, Dec 28, 2022 at 09:50

Wednesday, Dec 28, 2022 at 09:50
Thanks Andrew for the reply

Sounds good but as I mentioned I would only use the solar blanket on the odd occasion so the simplicity of a double anderson on the redarc suits my KISS philosophy !

Last camp I did with mates who run set ups with bluetooth connectivity spent half the time on their stupid effin phone monitoring their batteries and panel output - which annoys the crap out of me !!

The way I check my battery level is to get a beer out of the fridge and if it's cold the battery is still good and after 2-3 days I grab a beer out of the fridge and it's not cold then I know the battery needs charging.

Thanks again

Cheers and cold beers
Gazz


3
FollowupID: 921955

Sponsored Links